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US-12622687-B2 - Lateral retractor system for minimizing muscle damage in spinal surgery

US12622687B2US 12622687 B2US12622687 B2US 12622687B2US-12622687-B2

Abstract

A lateral retractor system for forming a pathway to a patient's intervertebral disc space includes a single dilator and a retractable dual-tapered-blade assembly. The dilator may feature a narrow rectangular body for insertion at an insertion orientation parallel to the fibers of the patient's psoas muscle, at an approximate 45-degree angle to the patient's spine. The retractable dual-tapered-blade assembly consists of only two blade subassemblies, each having a blade bordered by adjustable wings, along with built-in lighting and video capabilities. The dual-tapered-blade assembly may be passed over the single dilator at the insertion orientation and rotated approximately 45-50 degrees to a final rotated orientation parallel to the intervertebral disc space before the two blade subassemblies are retracted away from one another to create the surgical pathway, while simultaneously and continuously assessing for encroachment upon one or more nerve structures within 360-degrees of the instrument. Other embodiments are also disclosed.

Inventors

  • Edward Rustamzadeh

Assignees

  • Edward Rustamzadeh

Dates

Publication Date
20260512
Application Date
20240515

Claims (20)

  1. 1 . A lateral retractor system for forming a surgical pathway through a plurality of psoas muscle fibers to a patient's intervertebral disc space, comprising: a dilator including: a conductive body extending between a proximal end and a distal end; a first nonconductive layer disposed upon an outer surface of the conductive body; a first active neuromonitoring tip protruding from the distal end of the conductive body to a leading distal edge configured for insertion into the intervertebral disc space; and a first conductive electrical pathway extending from a first conductive input surface at the proximal end of the conductive body, through the conductive body, and to the first active neuromonitoring tip such that an electrical signal applied to the first conductive input surface causes the first active neuromonitoring tip to simultaneously and continuously stimulate one or more nerve structures located adjacent to any portion of a circumference of the distal end of the conductive body to assess for an encroachment of the dilator upon the one or more of the nerve structures.
  2. 2 . The lateral retractor system of claim 1 , wherein the first nonconductive layer and the conductive body are a single material.
  3. 3 . The lateral retractor system of claim 2 , wherein the single material includes an anodized layer forming the nonconductive layer.
  4. 4 . The lateral retractor system of claim 3 , wherein the single material is aluminum.
  5. 5 . The lateral retractor system of claim 1 , further comprising a retractable dual-blade assembly having two blade subassemblies, each of the blade subassemblies comprising: a conductive blade body having a planar inner-facing surface, an outer-facing surface, and opposing longitudinal edges extending from a proximal end to a distal end of the conductive blade body, the retractable dual-blade assembly configured to pass over the dilator; a second nonconductive layer disposed upon an outer surface of the conductive blade body; a second active neuromonitoring tip protruding from the distal end of the conductive blade body; and a second conductive electrical pathway extending from a second conductive input surface at the proximal end of the conductive blade body, through the conductive blade body, and to the second active neuromonitoring tip such that a second electrical signal applied to the second conductive input surface causes the second active neuromonitoring tip to simultaneously and continuously stimulate one or more nerve structures located adjacent to any portion of a circumference of the distal end of the conductive blade body to assess for an encroachment of the distal end of the conductive blade body upon the one or more of the nerve structures.
  6. 6 . The lateral retractor system of claim 5 , each of the blade subassemblies further comprising an adjustable wing rotatively coupled with each of the opposing longitudinal edges of the conductive blade body via at least one conductive hinge, each of the adjustable wings configured to move between an open position parallel to the inner-facing surface of the conductive blade body and a closed position perpendicular to the inner-facing surface of the conductive blade body, wherein each of the adjustable wings comprises: a conductive wing body having a planar inner-facing surface and an outer-facing surface extending from a proximal end to a distal end of the conductive wing body; a third nonconductive layer disposed upon an outer surface of the conductive wing body; and a third active neuromonitoring tip protruding from the distal end of the conductive wing body, the second conductive pathway extending from the second conductive input surface at the proximal end of the conductive blade body, through the at least one conductive hinge, through the conductive hinge body, and to the third active neuromonitoring tip such that the second electrical signal applied to the second conductive input surface causes the third active neuromonitoring tip to simultaneously and continuously stimulate one or more nerve structures located adjacent to any portion of a circumference of the distal end of the conductive wing body to assess for an encroachment of the conductive wing body upon the one or more of the nerve structures.
  7. 7 . The lateral retractor system of claim 6 , wherein the third active neuromonitoring tip has a maximum active width that equals a width of the conductive wing body.
  8. 8 . The lateral retractor system of claim 6 , wherein the first and the second conductive electrical pathways are free of conductive wiring.
  9. 9 . A dilation system for minimizing damage to a patient's psoas muscle fibers when forming a surgical pathway to an intervertebral disc space of the patient's spine, the dilation system having a dilator including: a conductive body portion extending between a proximal end and distal end; a nonconductive layer disposed upon the conductive body portion; and a conductive neuromonitoring portion extending distally from the distal end of the conductive body portion to a leading distal edge configured for insertion between the patient's psoas muscle fibers, wherein when an electrical dilator stimulus is applied to the proximal end of the conductive body portion, the electrical dilator stimulus propagates through the conductive body portion to the conductive neuromonitoring portion such that the conductive neuromonitoring portion simultaneously stimulates one or more nerve structures located adjacent to any point about a circumference of the conductive neuromonitoring portion.
  10. 10 . The dilation system of claim 9 , wherein the nonconductive layer and the conductive body portion are a single material.
  11. 11 . The dilation system of claim 10 , wherein the single material includes an anodized layer forming the nonconductive layer.
  12. 12 . The dilation system of claim 11 , wherein the single material is aluminum.
  13. 13 . The dilation system of claim 9 , further comprising: a retractable blade assembly comprising opposing detachably-attached blades, each of the opposing detachably-attached blades configured to be passed over the dilator on either side of the two opposing flat surfaces of the dilator, each of the opposing detachably-attached blades including: a conductive body portion comprising an inner surface and an outer surface that extend between a proximal end and a distal end of each of the opposing detachably-attached blades; a nonconductive layer disposed upon the conductive body portion of each of the opposing detachably-attached blades; and a conductive neuromonitoring portion extending distally from the distal end of the conductive body portion of each of the opposing detachably-attached blades to a leading distal edge of each of the opposing detachably-attached blades, wherein when an electrical blade stimulus is applied to the proximal end of the conductive body portion of each of the opposing detachably-attached blades, the electrical blade stimulus propagates through the conductive body portion to the conductive neuromonitoring portion of each of the opposing detachably-attached blades such that the conductive neuromonitoring portion of each of the opposing detachably-attached blades simultaneously stimulates one or more nerve structures located adjacent to any point about a circumference of the conductive neuromonitoring portion of each of the opposing detachably-attached blades.
  14. 14 . The dilation system of claim 13 , wherein the nonconductive layer and the conductive body portion are a single material.
  15. 15 . The dilation system of claim 14 , wherein the single material includes an anodized layer forming the nonconductive layer.
  16. 16 . The dilation system of claim 15 , wherein the single material is aluminum.
  17. 17 . The dilation system of claim 9 , further comprising: an adjustable wing hingedly attached to each longitudinal edge of each of the opposing detachably-attached blades, each of the adjustable wings comprising: a conductive body portion comprising a planer inner surface and an outer surface that extend between a proximal end and a distal end of each of the adjustable wings; a nonconductive layer disposed upon the conductive body portion of each of the adjustable wings; and a conductive neuromonitoring portion extending distally from the distal end of the conductive body portion of each of the adjustable wings to a leading distal edge of each of the adjustable wings, wherein when the electrical blade stimulus is applied to the proximal end of the conductive body portion of each of the adjustable wings, the electrical blade stimulus propagates through the conductive body portion to the conductive neuromonitoring portion of each of the adjustable wings such that the conductive neuromonitoring portion of each of the adjustable wings simultaneously stimulates one or more nerve structures located adjacent to any point about a circumference of the conductive neuromonitoring portion of each of the adjustable wings.
  18. 18 . The dilation system of claim 17 , wherein the nonconductive layer and the conductive body portion are a single material.
  19. 19 . The dilation system of claim 18 , wherein the single material includes an anodized layer forming the nonconductive layer.
  20. 20 . The dilation system of claim 19 , wherein the single material is aluminum.

Description

REFERENCE TO PENDING PRIOR PATENT APPLICATION This application is a continuation of pending prior U.S. patent application Ser. No. 17/158,155, filed Jan. 26, 2021 by Edward Rustamzadeh for “LATERAL RETRACTOR SYSTEM FOR MINIMIZING MUSCLE DAMAGE IN SPINAL SURGERY” which is a continuation-in-part of prior U.S. patent application Ser. No. 16/988,901, filed Aug. 10, 2020 by Edward Rustamzadeh for “LATERAL RETRACTOR SYSTEM FOR MINIMIZING MUSCLE DAMAGE IN SPINAL SURGERY” and issued as U.S. Pat. No. 10,925,593 on Feb. 23, 2021, which is a continuation-in-part of prior U.S. patent application Ser. No. 16/533,368, filed Aug. 6, 2019 by Edward Rustamzadeh for “LATERAL RETRACTOR SYSTEM FOR MINIMIZING MUSCLE DAMAGE IN SPINAL SURGERY,” and issued as U.S. Pat. No. 10,799,230 on Oct. 13, 2020, which is a continuation of prior U.S. patent application Ser. No. 16/356,494, filed Mar. 18, 2019 by Edward Rustamzadeh for “LATERAL RETRACTOR SYSTEM FOR MINIMIZING MUSCLE DAMAGE IN SPINAL SURGERY” and issued as U.S. Pat. No. 10,426,452 on Oct. 1, 2019, which is a divisional of prior U.S. patent application Ser. No. 16/273,322, filed Feb. 12, 2019 by Edward Rustamzadeh for “LATERAL RETRACTOR SYSTEM FOR MINIMIZING MUSCLE DAMAGE IN SPINAL SURGERY” and issued as U.S. Pat. No. 10,363,023 on Jul. 30, 2019, all of which patent application is hereby incorporated by reference. BACKGROUND The spine is a flexible column formed of a plurality of bones called vertebrae. The vertebrae are hollow and piled one upon the other, forming a strong hollow column for support of the cranium and trunk. The hollow core of the spine houses and protects the nerves of the spinal cord. The different vertebrae are connected to one another by means of articular processes and intervertebral, fibrocartilaginous bodies, or spinal discs. Various spinal disorders may cause the spine to become misaligned, curved, and/or twisted or result in fractured and/or compressed vertebrae. It is often necessary to surgically correct these spinal disorders. The spine includes seven cervical (neck) vertebrae, twelve thoracic (chest) vertebrae, five lumbar (lower back) vertebrae, and the fused vertebrae in the sacrum and coccyx that help to form the hip region. While the shapes of individual vertebrae differ among these regions, each is essentially a short hollow shaft containing the bundle of nerves known as the spinal cord. Individual nerves, such as those carrying messages to the arms or legs, enter and exit the spinal cord through gaps between vertebrae. The spinal discs act as shock absorbers, cushioning the spine, and preventing individual bones from contacting each other. Discs also help to hold the vertebrae together. The weight of the upper body is transferred through the spine to the hips and the legs. The spine is held upright through the work of the back muscles, which are attached to the vertebrae. A number of approaches, systems, and apparatuses have been devised to accomplish a variety of surgical interventions in association with the spine. These approaches enable a surgeon to place instrumentation and implantable apparatuses related to discectomy, laminectomy, spinal fusion, vertebral body replacement and other procedures intended to address pathologies of the spine. The variety of surgical approaches to the spine have a number of advantages and drawbacks such that no one perfect approach exists. A surgeon often chooses one surgical approach to the spine from a multitude of options dependent on the relevant anatomy, pathology, and a comparison of the advantages and drawbacks of the variety of approaches relevant to a particular patient. A common surgical approach to the spine is the lateral approach, which, in general, requires a surgeon to access the spine by creating a surgical pathway through the side of the patient's body through the psoas muscle to an intervertebral disc space where it is possible to dock onto the lateral lumbar disc. Variants of the lateral approach are commonly referred to as the “direct lateral” approach in association with the “DLIF” procedure, the “extreme lateral” approach in association with the “XLIF” procedure, and the “oblique lumbar” approach in association with the “OLIF” procedure. A common problem associated with the lateral surgical approach includes a significant risk of damage to the musculature surrounding the spine. FIGS. 1A-1B illustrates a partial view of a spine 100 comprised of sequential vertebrae 109, each separated by intervertebral disc space 110, with an attached psoas muscle group 102 (including the psoas minor and psoas major). As shown, the psoas muscle 102 runs generally in a cranial-caudal direction with muscle fibers attached diagonally or at an approximate 45-degree angle to the spine 100. FIGS. 2A-2B illustrate an exemplary lateral approach to the spine. In typical lateral approaches, after making an incision in the psoas muscle 102, the surgeon places a number of sequential circular dilators 1041-n, each lar