# K974749: Synergy Closed Variable Locking Screw (VLS), Part of the Cross Medical-Synergy Anterior and Posterior Spinal Systems

- Pathway: 510(k) (Traditional)
- Applicant: Cross Medical Products, Inc.
- Decided: Mar 13, 1998 after 84 days
- Product code: MNH (Orthosis, Spondylolisthesis Spinal Fixation)
- Device class: 2
- Regulation: 21 CFR 888.3070
- Recalls of this device: none
- Data: FDA decisions to Oct 25, 2026; recalls to Oct 12, 2026

## Lineage
Longest line of descent: 3 generations back to K901587 (1990). 14 ancestors in all.
311 later devices descend from it; 20 cite it directly.
0 of 326 devices in its family (counting itself) have a Class I recall.

## Predicates on the family tree (from the FDA summary)
- K934429: Anterior Spine System, Buckman Co., Inc. (1994) Summary page 2.
- K950709: Synergy TI Anterior Spinal System, Cross Medical Products, Inc. (1995) Summary page 2.
- K940631: Cross Medical - Synergy (TM) Spine System, Cross Medical Products, Inc. (1995) Summary page 2.
- K950099: Synergy (TM) TI Posterior Spinal System, Buckman Co., Inc. (1997) Summary page 2.
- K973836: Synergy 6.35MM SS Rod with Screws for Anterior Use, Part of the Cross Medical-Synergy Anterior Spinal System, Cross Medical Products, Inc. (1998). Cleared while this submission was under review Summary page 2.

## Most influential descendants
- K993503: Haider-Ucr Spinal System (2000), 176 descendants of its own
- K021623: Ucr Spinal System, 5.5MM, 8.0MM Screws & Instruments (2002), 175 descendants of its own
- K032739: Ucr Spinal System (2003), 174 descendants of its own
- K101278: Inertia Pedicle Screw System (2010), 111 descendants of its own
- K132412: Inertia Mis Pedicle Screw System (2013), 107 descendants of its own

## Indications for use
As a pedicle screw system, it is intended only for patients: (a) having severe spondylolisthesis (Grades 3 and 4) of the fifth lumbar-first sacral (L5-S1) vertebral joint; (b) who are receiving fusions using autogenous bone graft only; © who are having the screws fixed or attached to the lumbar and sacral spine; and (d) who are having the device removed after the development of a solid fusion mass. The levels of screw fixation are L3 to S1/Ilium. As a posterior, non-pedicle screw and hook system, and an anterolateral, intervertebral body screw system, the specific indications are: 1. Degenerative Disc Disease (as defined by chronic back pain of discogenic origin with degeneration of the disc confirmed by history and radiographic studies). Idiopathic scoliosis. Kyphotic deformities of the spine. Paralytic scoliosis and/or pelvic obliquity. Lordetic deformities of the spine. Neuromuscular scoliosis associated with pelvic obliquity. Vertebral fracture or dislocation. Tumors. Spondylolisthesis. 10 Stenosis. 11. Pseudarthrosis. 12. Unsuccessful previous attempts at spinal fusion. For posterior, non-pedicle screw use, the levels of use are T1 to the Sacrum/Ilium. For anterior use, the levels of use are T10 to L3 for the double rod constructs, and T5 to LS5 for the single rod constructs.

Source page: https://510kreport.com/device/K974749
Methodology: https://510kreport.com/methodology