SK™ Range of Motion (ROM™) Hinge
Another recent development in hinged transarticular external skeletal fixation (TESF) is the release of two sizes of a range of motion (ROM™) hinge. These hinges combine an adjustable joint angle into a lockable TESF hinge that can allow a variable range of motion as selected by the surgeon. Various versions of this device have been utilized in research projects and have also made their way into limited clinical use. Since beta users have requested additional frames, IMEX™ has made two sizes of this adjustable ROM™ (Range of Motion) hinge available. However, other than describing the devices and components, it is beyond the scope of this product release to provide surgical training in use of these components. Small and large ROM™ hinges are available and designed to be modular with SK™ ESF components.
Both ROM™ hinges feature a multi-toothed locking nut that allows the surgeon to lock in any desired starting position or “normal standing angle.” The opposite end of the ROM™ hinge body features a central flat that determines locked position, and two adjacent arcs that allow for a variable degree of motion to be dialed in as desired. The ability to progressively increase the allotted range of motion during the healing period is unique to the IMEX™ ROM™ hinge and can be utilized or ignored depending on patient management requirements.
The small ROM™ hinge utilizes standard 6.3mm SK™ titanium hybrid rods as the external bars that support small SK™ clamps. These rods are available in 50mm length increments from 50mm to 250mm and allow the surgeon to customize overall hinged fixator length to the patient’s anatomy.
The large ROM™ hinge uses special titanium hinge rods with 8mm threads and a 9.5mm rod diameter. The threads are larger in diameter than standard large hybrid rods. This diameter was chosen to increase the strength of the threaded portion and reduce potential for rod failure as compared to large SK™ hybrid rods. These rods are available in 75mm, 100mm, 150mm and 200mm overall lengths allowing the surgeon to customize hinged fixator length when utilizing large SK™ ESF clamps. Each ROM™ hinge comes pre-assembled with two rods representing typical applications. Consider purchasing alternate rod lengths with initial order.
To change rods, loosen the corresponding nut or nuts and unscrew the rod from the corresponding hinge pin. This can usually be done by hand, but a pair of pliers can be used if needed. Since the hinge pin is held in position by the rod, it must be positioned before screwing in the replacement rod. The rod will screw into the hinge pin from only one side, so if difficulty is encountered try the other side. The small ROM™ hinge nuts utilize 10mm wrenches. The large ROM™ hinge utilizes 13mm and 15mm wrenches or a small, adjustable wrench.
| PART NO. | DESCRIPTION |
| 430.000 | Small SK™ Range of Motion (ROM™) Hinge |
| 530.000 | Large SK™ Range of Motion (ROM™) Hinge |
| ---------------- | --------------------------------------------- |
| 6.3MM sMALL HYBRID RODS | |
| 407.050 | 6.3mm x 50mm Titanium Hybrid Rod, 6mm Thread |
| 407.075* | 6.3mm x 75mm Titanium Hybrid Rod, 6mm Thread |
| 407.100* | 6.3mm x 100mm Titanium Hybrid Rod, 6mm Thread |
| 407.150 | 6.3mm x 150mm Titanium Hybrid Rod, 6mm Thread |
| 407.200 | 6.3mm x 200mm Titanium Hybrid Rod, 6mm Thread |
| 407.250 | 6.3mm x 250mm Titanium Hybrid Rod, 6mm Thread |
| ---------------- | --------------------------------------------- |
| 9.5MM LARGE SK™ ROM™ HINGE RODS | |
| 530.075 | 9.5mm x 75mm large SK™ ROM™ Hinge Rod, 8mm Thread |
| 530.100* | 9.5mm x 100mm large SK™ ROM™ Hinge Rod, 8mm Thread |
| 530.150* | 9.5mm x 150mm large SK™ ROM™ Hinge Rod, 8mm Thread |
| 530.200 | 9.5mm x 200mm large SK™ ROM™ Hinge Rod, 8mm Thread |
*Rod lengths included with standard assembly
Small ROM™ Hinge - 185mm (7.25
inches) - approximate overall length at 180 degrees
Large ROM™ Hinge - 260mm (10.25 inches) - approximate overall
length at 180 degrees
