Summary Intramedullary fixation is standard for many unstable pertrochanteric and subtrochanteric fractures. The Arthrex Trochanteric Nail System is a cephalomedullary construct available in short, extended-short (ES), and long configurations, with a telescoping lag screw, optional anti-rotation screw, and an augmentation system for biologic or cement injection through the lag screw tract. Indications and specifications in this review are summarized from the Arthrex Trochanteric Nail System surgical technique guide and related manufacturer materials. Key system concepts (manufacturer-described design features) Short, ES, and long trochanteric nails are intended to treat a broad spectrum of proximal femur fractures, with ES and long options extending into the diaphyseal isthmus. A 10.5 mm telescoping lag screw is designed to collapse within the screw itself, aiming to allow controlled fracture compression while limiting lateral screw prominence and soft-tissue irritation compared with conventional sliding constructs. The ES nail is intended to combine the mechanical stability of a long nail with the targeting simplicity of a short nail; it extends to and through the isthmus while using a jig-targeted distal hole rather than freehand locking. Manufacturer bench testing in simulated models has reported increased torsional rigidity of the ES configuration compared with certain long nail configurations; these data are preclinical and should be interpreted as design rationale rather than outcome evidence. Optional features include a 5.0 mm anti-rotation screw and a Trochanteric Nail Augmentation System that delivers flowable bone graft or cement through the lag screw tract into the femoral head. Indications Overall system indications According to manufacturer materials, the Arthrex Trochanteric Nail System is intended for stable and unstable proximal femoral fractures, including pertrochanteric, intertrochanteric, and high subtrochanteric patterns and combinations of these. Long trochanteric nail Subtrochanteric fractures. Pertrochanteric fractures with shaft extension. Pathologic fractures, including prophylactic stabilization, in osteoporotic trochanteric and diaphyseal bone. Long subtrochanteric fractures. Ipsilateral femoral fractures. Proximal and distal nonunions and malunions. Revision procedures after failed fixation. ES trochanteric nail Intended only for stable and unstable proximal femur fractures, including pertrochanteric, intertrochanteric, and high subtrochanteric fractures and combinations of these. Patients with femoral shaft fractures should not be treated with the ES nail; this limitation is stated explicitly in the technique guide and should be respected when choosing implants. Clinical context Short or ES nails are commonly used for low-energy osteoporotic intertrochanteric fractures in elderly patients where diaphyseal involvement is minimal. Long nails are more often used for high-energy subtrochanteric fractures, pertrochanteric fractures with shaft extension, and combined proximal and shaft injuries in younger or higher-demand patients. Anatomy Osteology The proximal femur comprises the femoral head, neck, greater and lesser trochanters, intertrochanteric region, and proximal diaphysis. The head–neck segment articulates with the acetabulum, and the neck–shaft angle is typically within the range that corresponds to the system’s 125-degree and 130-degree CCD options. Key anatomic considerations for this system Entry point The recommended entry is at the tip of the greater trochanter on the AP view, potentially slightly medial depending on patient morphology. On the lateral view, the entry is at the junction of the anterior and middle third of the greater trochanter to facilitate access into the femoral neck. Canal alignment The long and ES nails incorporate an anterior bow to better follow the femoral canal and reduce the risk of anterior cortical impingement. Isthmus For ES and long nails, extension through the isthmus distributes stress more distally and is intended to reduce distal tip stress risers. Muscles Muscle attachments around the trochanteric region are central to fracture displacement and reduction. Gluteus medius and gluteus minimus Insert on the greater trochanter. Abductor tension contributes to varus and external rotation of the proximal fragment. Short external rotators (piriformis, obturator internus, obturator externus, superior and inferior gemellus) Attach near the posterior greater trochanter and posterior neck. Drive external rotation of the proximal fragment. Iliopsoas Inserts on the lesser trochanter. Can flex and externally rotate the proximal fragment. Vastus lateralis Originates along the lateral proximal femur. Can tether distal fragments. These force vectors explain the propensity toward varus and rotational malalignment in intertrochanteric fractures and underscore the need for careful reduction before nail insertion. Ligaments The iliofemoral, pubofemoral, and ischiofemoral ligaments form a capsuloligamentous envelope that confers intrinsic hip stability. In trochanteric fractures, the capsule is usually intact. Fixation aims to restore mechanical alignment and permit early weight bearing while relying on preserved ligamentous stability rather than altering the capsule itself. Nerves Structures at risk around the approach include Superior gluteal nerve At risk with excessive proximal dissection through the abductors. Sciatic nerve Generally posterior. Risk increases with posterior exposures or freehand distal locking approaches posterior to the femur. Femoral and lateral femoral cutaneous nerves At risk with very anterior incisions or retractors around the anterior hip. The standard trochanteric approach with limited lateral incisions and percutaneous distal locking minimizes direct nerve exposure. Blood supply The femoral head and neck receive blood primarily from the medial and lateral circumflex femoral arteries via retinacular branches that run along the femoral neck, supplemented by intraosseous vessels and contributions from the ligamentum teres. Avoiding guidewire or lag screw perforation of the subchondral bone is critical to protect remaining vascularity and limit articular damage. Manufacturer technique emphasizes stopping the guidewire about 5 mm short of the subchondral bone and maintaining central or slightly inferior and posterior placement in the femoral head. Approach Patient positioning Patients are typically positioned supine on a fracture or traction table. A radiolucent flat-top table can be used in select cases, with manual traction and reduction. Traction and rotation are applied to restore length, alignment, and version. Imaging A true AP of the proximal femur and lateral of the hip are mandatory. C-arm positioning should allow access to both proximal and distal locking zones. Incision and entry The proximal incision is made over the tip of the greater trochanter. A soft-tissue protector with a pin guide is used to place an entry guide pin at the recommended point AP view Tip of the greater trochanter or slightly medial. Lateral view Junction of anterior and middle third of the greater trochanter. The entry portal is created with a cannulated entry reamer or a curved cannulated awl. Depth grooves on the entry reamer correspond to nail seating flush, 5 mm recessed, or 10 mm recessed relative to the lateral cortex. Reduction Reduction should be optimized before canal instrumentation. A dedicated reduction tool sometimes referred to as a fracture finger and percutaneous clamps can be helpful, particularly for subtrochanteric or multi-fragmentary patterns. Technique Entry and guidewire placement After entry reaming, a ball-nose guidewire is advanced down the canal. For long or ES nails, the guidewire is passed across any diaphyseal fracture. A guidewire gripper and reduction tool assist in aligning proximal and distal segments. Reaming is usually unnecessary for short nails. Reaming is recommended for ES and long nails, beginning with an end-cutting reamer followed by side-cutting reamers, typically 1–1.5 mm over the planned nail diameter. Nail selection and insertion Nail length for ES and long nails is determined with a guidewire depth gauge. Short nails are typically 20 cm in length, with some shorter special-order options. ES and long nails are available in multiple lengths from approximately 30–42 cm. The chosen 125-degree or 130-degree nail is attached to a radiolucent targeting arm. For ES and long nails, the targeting arm is held anterior during insertion and then rotated laterally as the bow passes through the femur, helping the nail follow the canal curvature. Short nails lack an anterior bow and can be inserted with the jig lateral to the thigh. Gentle malleting is performed on the impactor pad rather than on the targeting arm. Lag screw guide pin and measurement With the nail seated, a triple-sleeve assembly consisting of lag screw sheath, pin guide, and obturator is snapped into the targeting arm. The assembly is advanced through a small lateral incision to the lateral cortex, and the obturator is removed. A 3.2 mm guide pin is then driven into the femoral head. Ideal guide pin position AP view Central or slightly inferior in the head. Lateral view Central or slightly posterior. Depth Tip kept about 5 mm short of the subchondral bone. Lag screw length and reaming depth are determined with a dual-sided lag screw depth gauge One side measures reaming depth from the pin guide to the wire tip. The other side accounts for the position of the internal locking ring when the screw is advanced to the pin tip. A legacy depth gauge is also available but requires manual subtraction to account for subchondral clearance and planned compression. Anti-rotation bar (optional) If the femoral head fragment is unstable during instrumentation, an anti-rotation triple-sleeve can be introduced through a separate targeting arm hole. A calibrated 5.0 mm step drill is used to the desired depth, typically at least 10–15 mm shorter than the anticipated lag screw length. A radiopaque anti-rotation bar is placed provisionally to limit head rotation while the lag screw is prepared. Canal preparation and lag screw insertion The adjustable stop on the cannulated lag screw drill is set to 5–10 mm shorter than the measured depth so the drill tip remains short of the guidewire tip. The femoral head is reamed through the lag screw sheath. A lag screw tap is available if needed in dense bone. The 10.5 mm telescoping or solid locking lag screw is coupled to the inserter via a capturing rod and a castle-type interface, with alignment marks confirming proper engagement. The lag screw is advanced over the guide pin until a laser mark on the inserter aligns with the sheath, indicating the screw has passed fully through the sheath. If intraoperative compression is planned, the screw should be countersunk appropriately to provide room for sliding before the internal locking ring engages. Compression and locking A compression sleeve on the inserter is advanced toward the targeting arm and rotated clockwise to apply fracture compression through the telescoping screw. If the screw has been advanced too far laterally to lock, the mechanism free-spins and displays a red line in the handle window, signaling that additional screw advancement into the head is required before compression can be completed. Once the desired compression is achieved, the integrated locking knob is engaged. Holding the main handle stationary, the locking handle is turned clockwise until a torque limiter clicks, indicating that the telescoping or solid lag screw is locked to the nail without a separate set screw. For telescoping screws, an internal activation sleeve can be removed with a dedicated tool to permit postoperative controlled collapse. Leaving the activation sleeve in place prevents further telescoping. Anti-rotation screw (optional) If persistent rotational instability is present, a 5.0 mm cancellous anti-rotation screw can be inserted over the provisional drill tract, using the same anti-rotation triple-sleeve. The manufacturer recommends choosing an anti-rotation screw at least 10 mm shorter than the lag screw to minimize the risk of joint penetration. Distal locking Short and ES nails Distal locking is performed via the targeting arm using a triple-sleeve and a calibrated drill. Screw length is measured directly from the drill markings. Captured 5.0 mm cortical screws are then inserted. Markings on the driver indicate when the screw head clears the sheath. Long nails Freehand perfect circles technique is used with fluoroscopic guidance. Length can be confirmed with a distal depth gauge or hook-tip depth gauge. Long and ES nails incorporate a distal dynamization slot, allowing the surgeon to choose static locking or dynamic distal locking based on fracture pattern and desired controlled axial motion. End caps Optional captured end caps with different proudness, such as flush, plus 5 mm, and plus 10 mm, are available. End caps protect proximal nail threads and adjust proximal prominence relative to the greater trochanter. Biologic augmentation optional The Trochanteric Nail Augmentation System consists of a longer guide pin, a delivery cannula, and syringes designed for flowable allograft or synthetic bone void fillers, as well as cements and autologous blood-derived products. Key steps for augmentation Use the longer guide pin from the augmentation kit for lag screw placement and reaming. Insert the lag screw but stop approximately 10 mm short of its final position. Advance the delivery cannula through the inserter so that its calibration mark matches the selected lag screw length; the cannula tip then projects beyond the screw tip into the femoral head and this position should be confirmed on fluoroscopy. After removing the inner trocar, inject the chosen flowable graft through the cannula, verifying extra-articular distribution and ensuring the femoral head has not been perforated by the guidewire or cannula; if perforation is seen, augmentation should be abandoned. Reinsert the trocar to clear the cannula, then advance the lag screw through the graft to the desired tip–apex position before completing locking and any anti-rotation screw placement. Evidence for augmentation-related improvements in clinical outcomes remains limited; decisions to augment should be individualized based on bone quality and perceived risk of cut-out. Pearls system-specific Confirm indications carefully and avoid using the ES nail in any fracture with significant shaft involvement; choose a long nail instead in these scenarios. For ES and long nails, start insertion with the targeting arm anterior and rotate laterally as the bow advances to better match the femoral curvature. When planning compression with the telescoping screw, intentionally choose a slightly shorter lag screw and countersink the lateral edge to create space for sliding. Use the lag screw depth gauge rather than relying solely on fluoroscopic estimation to keep the locking ring centered within the nail at final position. Before augmentation, verify on fluoroscopy that the guidewire and cannula have not perforated the femoral head. Pitfalls Accepting varus malreduction or failure to restore neck–shaft angle before nail insertion, which the system cannot fully correct once the nail is seated. Allowing the lag screw to remain excessively lateral; the compression mechanism will not lock and will show a red-line free-spinning indicator, forcing revision of screw depth. Under-reaming the canal for ES or long nails, which can impede insertion and risk iatrogenic fracture. Over-reaming the canal excessively, which may compromise construct stability. Choosing an anti-rotation screw the same length as the lag screw, increasing the chance of joint penetration. Using short nails for long subtrochanteric or combined shaft patterns, which may increase the risk of distal stress risers and peri-implant fracture. Technical Specifications Shared design parameters All three nail types share several design parameters. CCD angles of 125 degrees and 130 degrees. Built-in lateralization and anteversion of the proximal segment to match typical femoral anatomy. Compatibility with 10.5 mm lag screws, telescoping or solid, and 5.0 mm distal and anti-rotation screws. Length and diameter ranges standard offerings; some sizes may be special-order Short nails Length around 20 cm. Some shorter special-order options are available. Diameters typically 9–13 mm. ES nails Lengths in the 30–42 cm range. Diameters commonly 10 and 11 mm. Larger diameters, such as 12.5 and 14 mm, may be available as special order. Long nails Lengths approximately 30–42 cm. Standard diameters of 10 and 11 mm. Larger options, for example 12.5 mm, may be available as special order. Additional features Long and ES nails include a distal dynamization slot; short nails do not. End caps in different proudness options allow adjustment of the effective proximal prominence and protection of proximal threads. These specifications are paraphrased from Arthrex technical data and may be updated with future system revisions. Screws Lag screws The primary cephalic fixation is a 10.5 mm lag screw available in a range of lengths, typically around 85–120 mm in 5 mm increments. Telescoping lag screw variants incorporate an internal mechanism that permits controlled shortening within the screw body. Compression can be applied intraoperatively and, if the activation sleeve is removed, continued postoperatively as the fracture settles. A 10.5 mm solid locking lag screw is also available for surgeons who prefer a fixed-angle construct without telescoping. Lag screw length is selected to achieve a low tip–apex distance while respecting the 5 mm subchondral buffer. Anti-rotation screws Anti-rotation screws are 5.0 mm cancellous screws offered in a range of lengths, approximately 60–110 mm. They are inserted through a dedicated proximal hole and are intended to augment rotational control of the femoral head–neck fragment. They may be particularly useful in basicervical patterns or in good-quality bone where a single lag screw may not adequately control rotation. The manufacturer recommends selecting an anti-rotation screw at least 10 mm shorter than the lag screw to reduce articular penetration risk. Distal screws and end caps Distal fixation is achieved with 5.0 mm captured cortical screws in a broad length range. These screws are designed to remain attached to the driver during insertion and removal, simplifying percutaneous work. Depending on fracture pattern, the surgeon can choose static locking or use the dynamization slot on ES and long nails to allow controlled axial motion. Captured end caps with varying proudness complete the construct by preserving proximal threads and tuning the proximal profile relative to the greater trochanter. Biomechanical rationale From a biomechanical standpoint, the screw options in this system are intended to address common failure modes of cephalomedullary fixation, including lag screw cut-out, loss of reduction, and peri-implant fracture. This is pursued through controlled telescoping of the lag screw, optional rotational augmentation with anti-rotation screws, and diaphyseal extension with appropriate distal locking. These attributes should be viewed as manufacturer-stated design goals rather than proven superiority statements over other systems.