Welcome to the Neuromuscular Pathology Lab at the University of Colorado | Anschutz Medical Campus

Muscle Biopsy

For optimal results, we recommend following these steps:

1. Identify a muscle which is mildly to moderately weak (MRC grade 4- to 4+) since weaker muscle often only show nonspecific end stage changes. Muscles which are commonly biopsied and have normative histopathological data include the deltoid, biceps, quadriceps (vastus lateralis) and gastrocnemius muscles. The gastrocnemius has more variation and often wound healing is more difficult compared to other sites. Please contact us if you are unable to decide on which muscle to biopsy before beginning biopsy and we will try to assist you.
2. Relative contraindications to having a muscle biopsy include patients with a bleeding diathesis or receiving anticoagulation are best assessed by the surgeon performing the procedure.
3. When anesthetizing the skin and subcutaneous tissue, do not infiltrate the muscle with the anesthetic, this can cause artifactual findings.
4. Isolate a 15 mm long specimen with a diameter of at least 7-10mm (roughly 1 cm³). Sutures around the width of the specimen helps us orient it correctly.
5. Please submit 7-10 mm diameter of the muscle biopsy if possible.
6. **Put muscle biopsy directly onto the specimen cup without saline or gauze**
                                                    DO NOT SOAK THE SPECIMEN IN SALINE. 
                                                    DO NOT FLOAT THE SPECIMEN IN SALINE.
   
7. We strongly discourage the use of muscle clamps, as this induces trauma and consequently, unacceptable levels of artifact.
8. If the specimen is to be delivered within the hour (cab, courier) it can be sent at room temperature. If overnight delivery is necessary, place the container in a Styrofoam box and surround it with coolant packs (Blue Ice). Do not send on wet ice, as it tends to melt through the box. Request priority overnight delivery. It is important to notify our office that a biopsy is expected, so that we can trace missing packages quickly.

Nerve Biopsy Procedure and handling:

1. Relative contraindications to having a nerve biopsy such as bleeding diathesis are best assessed by the surgeon performing the procedure.
2. Please submit (1) one 20 mm long specimen of the sural nerve for full interpretation.
3. Wet gauze with saline and wring out excess saline. Place nerve biopsy in moist gauze and put it in a specimen cup. Do NOT SOAK or float the specimen in saline. Too much saline causes disruption and freeze artifact.
4. If the specimen is to be delivered within the hour (cab, courier) it can be sent at room temperature. If overnight delivery is necessary, place the containers in a Styrofoam box and surround it with coolant packs (Blue Ice). Do not send on wet ice, as it tends to melt through the box. Request priority overnight delivery. It is important to notify our office that a biopsy is expected, so that we can trace missing packages quickly.

Please contact us with questions that you have at the Neuromuscular Pathology Laboratory at (303) 724-4346.  

Varun Sreenivasan
CU Neuromuscular Pathology Lab Director
Neuromuscular Division, Department of Neurology
University of Colorado School of Medicine
Anschutz Medical Campus
Phone: (303) 724-2188
Fax: (303) 724-2202