# K191995: S4 Screw System

- Pathway: 510(k) (Traditional)
- Applicant: Subchondral Solutions, Inc.
- Decided: Apr 18, 2020 after 267 days
- Product code: HWC (Screw, Fixation, Bone)
- Device class: 2
- Regulation: 21 CFR 888.3040
- Recalls of this device: none
- Data: FDA decisions to Oct 25, 2026; recalls to Oct 12, 2026

## Lineage
Longest line of descent: 9 generations back to K962823 (1996). 90 ancestors in all.
2 later devices descend from it; 2 cite it directly.
0 of 93 devices in its family (counting itself) have a Class I recall.

## Predicates on the family tree (from the FDA summary)
- K162171: S4 Screw System™, Subchondral Solutions (2017) Summary page 4.
- K123890: Acumed Cannulated Screw System, Acumed, LLC (2013) Summary page 4.
- K171595: M.U.S.T. Sacral Iliac Screw and Pelvic Trauma System, Medacta International S.A. (2017) Summary page 4.

## Most influential descendants
- K231649: Intraosseous Fusion Device System (2023), 0 descendants of its own
- K220901: S-Core Implant System (2022), 0 descendants of its own

## Indications for use
Minimally invasive reconstruction of fractures and joints; Adjuvant for osteosynthesis in complex joint fractures; Multifragment joint fractures; Simple metaphyseal fractures, Fractures of the wrist, ankle, elbow, and shoulder, Condylar fractures; Osteochrondritis dissecans, Ostero-Chondral Fractures, Ligament avulsion injuries, Ligament fixation, Other small fragment, cancellous bone fractures, Small joint fusion. Areas where accurate screw placement is vital. Metatarsal and phalangeal osteotomies; Fractures of the tarsals, metatarsals and other fractures of the foot; Avulsion fractures and fractures of metatarsal V; Tarso-metatarsal and metatarso-phalangeal arthrodesis; Tarsal Fusions; Calcaneal and talar fractures, Subtalar arthrodesis, Ankle arthrodesis. Fractures of small joints, such as: Ankle fractures, Navicular fractures, Fractures of the fibula, malleolus, and calcaneus, Distal tibia and pilon fractures, Acetabular fractures. Other fractures of the pelvic ring; Fractures of the femoral head and neck, Supracondylar femoral fractures, Slipped capital femoral epiphyses, An adjunct to DHIS in basilar neck fractures, Intercondylar femur fractures, Intracapsular fractures of the hip, Fractures of the distal femur and proximal tibia, Patellar fractures, Tibial plateau fractures. Small fragments of the hand and wrist, Fractures of the carpals and metacarpals, Carnal and metacarpal arthrodesis, Scaphoid fracture and other fractures of the hand, Phalangeal and interphalangeal fractures, Fractures of the ulna and radius. Radial head fractures, Fractures of the olecranon and distal humerus, Humeral head fractures, Ligament fixation at the proximal humerus, Glenoid fractures.

Source page: https://510kreport.com/device/K191995
Methodology: https://510kreport.com/methodology