Cannulated screws femoral neck: Definition, Uses, and Clinical Overview

Cannulated screws femoral neck Introduction (What it is)

Cannulated screws femoral neck are hollow (cannulated) metal screws used to stabilize the femoral neck portion of the hip.
They are most commonly placed to fix certain femoral neck fractures by holding bone fragments in alignment.
The hollow center allows the screws to be inserted over guidewires for accurate positioning.
They are typically used in orthopedic trauma surgery and some hip-preservation procedures.

Why Cannulated screws femoral neck used (Purpose / benefits)

The femoral neck is the narrow “bridge” of bone between the femoral head (the ball) and the femoral shaft (the thighbone). When this region fractures, the goal of treatment is usually to restore alignment and stability so the bone can heal in the correct position while preserving hip function.

Cannulated screws femoral neck are used to:

• Stabilize a fracture internally (internal fixation) so the bone can heal with the correct alignment.
• Provide compression across the fracture line in many cases, which can support bone healing by reducing motion at the fracture site.
• Minimize surgical exposure compared with some alternative fixation methods, because cannulated screws are often placed percutaneously (through small incisions) using imaging guidance.
• Allow precise placement using guidewires and fluoroscopy (real-time X-ray), which helps surgeons confirm alignment and screw position during the operation.
• Preserve the patient’s native hip joint in situations where keeping the natural femoral head is considered appropriate, rather than replacing the joint.

The underlying problem these screws address is mechanical instability: when a fracture is not adequately stabilized, the fragments can shift, pain can persist, and healing may be delayed or unsuccessful. The screws function as internal supports to maintain alignment during the healing process.

Indications (When orthopedic clinicians use it)

Common scenarios where cannulated screws may be considered for femoral neck fixation include:

• Nondisplaced or minimally displaced femoral neck fractures (the bone alignment is largely maintained)
• Femoral neck fractures in younger patients, where preserving the native femoral head is often a priority (varies by clinician and case)
• Some femoral neck stress fractures, depending on fracture pattern and risk features (varies by clinician and case)
• Certain fracture patterns suitable for multiple-screw fixation, based on imaging and stability assessment
• Adjunct fixation in selected hip procedures, when a surgeon needs screw-based stabilization of the femoral neck region (varies by clinician and case)

Contraindications / when it’s NOT ideal

Cannulated screws are not a universal solution for all femoral neck injuries. Situations where they may be less suitable, or where another approach may be preferred, can include:

• Displaced femoral neck fractures in older adults, where arthroplasty (partial or total hip replacement) may be considered more predictable for function and complication avoidance (varies by clinician and case)
• Highly unstable fracture patterns, where a different fixation construct may provide better resistance to shear and rotation (varies by clinician and case)
• Comminution (the bone is broken into multiple fragments) that reduces the ability of screws alone to hold alignment
• Poor bone quality (osteoporosis) that may reduce screw purchase (grip) in the bone, prompting consideration of alternative fixation strategies (varies by clinician and case)
• Active infection near the surgical site, where implant placement may be delayed or modified
• Severe pre-existing hip arthritis or femoral head damage, where joint replacement may be more appropriate (varies by clinician and case)
• Inability to achieve or maintain acceptable fracture reduction, since accurate alignment is often critical for success

How it works (Mechanism / physiology)

Biomechanical principle

Cannulated screws stabilize the femoral neck primarily by resisting motion at the fracture site and, in many constructs, by compressing the fracture surfaces together. A common concept is the “lag screw” effect: when the screw threads engage one bone fragment while the screw head (or a washer) bears against the outer cortex, tightening can draw fragments together.

In femoral neck fixation, surgeons often use multiple screws (commonly arranged in a triangular pattern) to improve:

• Rotational control (preventing the femoral head fragment from twisting)
• Resistance to shear forces, especially in more vertically oriented fracture patterns
• Overall construct stiffness, which can help maintain alignment during healing

Relevant hip anatomy

Key structures involved include:

• Femoral head: the ball of the hip joint that must remain well positioned and well perfused.
• Femoral neck: the fracture site and the corridor where screws are placed.
• Hip capsule and retinacular vessels: soft tissues around the femoral neck that contribute to blood supply to the femoral head. Blood flow considerations are a major reason femoral neck fractures are treated carefully and urgently in many settings.
• Trabecular and cortical bone: internal “spongy” bone and outer “hard shell” bone that determine how well screws anchor.

Onset, duration, and reversibility

Cannulated screws provide immediate mechanical stabilization once placed. Their effect persists as long as the screws remain intact and well seated, and until the fracture heals.

• Duration: Implants may stay in permanently or be removed later, depending on symptoms, healing, surgeon preference, and case factors (varies by clinician and case).
• Reversibility: Hardware can often be removed, but removal is a separate procedure with its own considerations.

Cannulated screws femoral neck Procedure overview (How it’s applied)

Cannulated screws femoral neck describes an implant and fixation method rather than a single “test.” Below is a high-level, typical workflow. Exact steps vary by surgeon, hospital, and fracture pattern.

1. Evaluation / exam – History and physical exam after injury (or evaluation of stress-related hip pain) – Imaging, commonly X-rays; CT or MRI may be used in select cases to clarify fracture pattern or detect occult/stress fractures (varies by clinician and case) – Assessment of displacement, stability, patient factors, and treatment options

2. Preparation – Surgical planning for screw number, positioning, and length – Anesthesia planning and operating room setup – Positioning on the operating table and sterile preparation

3. Intervention – If needed, fracture reduction: aligning the fracture fragments before fixation (closed reduction using positioning/manipulation, or open reduction if required; varies by clinician and case) – Guidewire placement into the femoral head/neck under fluoroscopic guidance – Measurement and preparation of the screw track (drilling/reaming as appropriate) – Cannulated screw insertion over guidewires – Confirmation of alignment and screw position in multiple imaging views

4. Immediate checks – Final fluoroscopic images to confirm fracture reduction, screw depth, and positioning – Wound closure and dressing placement

5. Follow-up – Postoperative monitoring and scheduled imaging to assess healing and hardware position – Rehabilitation planning and progression of activity based on stability, healing, and clinician protocol (varies by clinician and case)

Types / variations

Cannulated screw systems differ by design and intended use. Common variations include:

• Partially threaded vs fully threaded screws
• Partially threaded designs are often used when compression across a fracture is desired.

• Fully threaded designs may be used when the goal is position-holding without additional compression, or in specific patterns where controlled compression is not desired (varies by clinician and case).

• Screw diameter and length

• Multiple sizes exist to match patient anatomy and bone quality (varies by material and manufacturer).

• Number of screws

• Many femoral neck constructs use two or three screws, though other configurations may be used in select cases (varies by clinician and case).

• Washer use

• Washers can increase the surface area under the screw head, which may be helpful in certain bone qualities or cortical conditions (varies by clinician and case).

• Material

• Common implant materials include stainless steel and titanium alloys. Choice may depend on surgeon preference, imaging considerations, and manufacturer system (varies by material and manufacturer).

• Headed vs headless designs

• Some screws are designed to sit more flush with bone, potentially reducing soft-tissue irritation in certain settings (varies by clinician and case).

Pros and cons

Pros:

• Minimally invasive placement is often possible (small incisions with imaging guidance).
• Allows precise screw positioning using guidewires and fluoroscopy.
• Can provide stable fixation and fracture compression in appropriate patterns.
• Preserves the patient’s native hip joint in selected cases.
• Widely used with established surgical workflows and implant systems.
• Hardware can often remain in place long-term if not symptomatic (varies by clinician and case).

Cons:

• Not ideal for all fracture types; unstable patterns may need different fixation or arthroplasty (varies by clinician and case).
• Femoral neck fractures have specific risks (such as healing problems and femoral head blood-supply concerns) that screws cannot fully eliminate.
• Hardware-related issues can occur, such as prominence/irritation, breakage, or loss of fixation (varies by clinician and case).
• Accurate reduction and placement are technically demanding and heavily imaging-dependent.
• May require activity restrictions and close follow-up while healing progresses (varies by clinician and case).
• Some patients later undergo hardware removal or conversion to arthroplasty if complications arise (varies by clinician and case).

Aftercare & longevity

Aftercare following femoral neck screw fixation focuses on protecting the repair while bone healing occurs and on monitoring for complications. Specific instructions vary by clinician and case, but common factors that influence outcomes and “longevity” of the fixation include:

• Fracture type and displacement

• Nondisplaced fractures generally behave differently than displaced fractures in terms of stability demands and healing risk.

• Quality of reduction and fixation

• Alignment and screw placement relative to the femoral head/neck anatomy can affect stability and the chance of maintaining position during healing.

• Bone quality

• Osteoporosis or other conditions affecting bone strength can reduce how well screws anchor.

• Weight-bearing status and activity level

• The amount and timing of loading through the hip can influence mechanical stress on the fixation. Postoperative weight-bearing recommendations vary by clinician and case.

• Rehabilitation and follow-up

• Physical therapy plans often emphasize safe mobility, gradual strengthening, and gait mechanics.

• Repeat imaging is commonly used to track fracture healing and hardware position over time.

• Patient health factors

• Smoking status, nutrition, metabolic bone health, and medical comorbidities can affect bone healing (general principle; impact varies by individual).

In terms of longevity, cannulated screws are designed to remain functional for the healing period and beyond. Some patients keep them indefinitely without issue, while others may have removal considered if there is persistent irritation, specific complications, or future hip surgery (varies by clinician and case).

Alternatives / comparisons

Treatment of femoral neck injuries depends heavily on fracture pattern, displacement, age, bone quality, and functional goals. Alternatives or comparisons to cannulated screw fixation include:

• Nonoperative management (observation, protected activity, or immobilization)

• In modern practice, many complete femoral neck fractures are treated surgically due to concerns about displacement and healing. Some stress fractures or very stable injuries may be managed without surgery in selected cases (varies by clinician and case).

• Sliding hip screw (dynamic hip screw)

• Uses a larger lag screw connected to a side plate, designed to allow controlled sliding/compression. It may offer advantages for certain fracture orientations and stability demands, but typically involves a larger incision and more soft-tissue exposure than percutaneous screws (varies by clinician and case).

• Cephalomedullary nail

• An intramedullary device commonly used for other proximal femur fractures; its role in true intracapsular femoral neck fractures differs by case and local practice (varies by clinician and case).

• Arthroplasty (hemiarthroplasty or total hip replacement)

• Often considered for displaced femoral neck fractures in older adults or when the femoral head is unlikely to remain viable or functional. It replaces part or all of the hip joint rather than relying on fracture healing.

• Other screw/plate constructs

• Fixed-angle devices or newer plating systems may be used for select patterns, especially where added angular stability is desired (varies by clinician and case).

Each option has different trade-offs in invasiveness, healing reliance, complication profile, and expected recovery trajectory. Choice is individualized and based on imaging, patient goals, and surgeon assessment.

Cannulated screws femoral neck Common questions (FAQ)

Q: Are cannulated screws the same as “pins”?
Cannulated screws are sometimes described loosely as “pins,” but they are threaded implants designed to hold bone and often create compression. Surgeons may also use smooth pins temporarily during reduction or as guidewires for screw placement. The terms are often mixed in casual conversation, but they are not identical.

Q: Will I be able to feel the screws inside my hip?
Many people do not feel internal screws once early healing has progressed. Some patients may notice discomfort from hardware prominence or irritation, depending on anatomy and screw position. Whether this happens varies by clinician and case.

Q: How long do cannulated screws stay in the femoral neck?
They may remain indefinitely if they are not causing symptoms and the fracture heals as expected. In other cases, a clinician may discuss removal after healing or if problems occur. The timing and indications vary by clinician and case.

Q: Is the surgery considered major surgery?
Fixation of a femoral neck fracture is typically treated as a significant orthopedic operation because it involves the hip, anesthesia, and the need for precise alignment and stabilization. Cannulated screw placement can be less invasive than some alternatives, but it is still a surgical procedure with risks that must be monitored.

Q: How painful is recovery after femoral neck screw fixation?
Pain levels vary widely based on the initial injury, surgical approach, and individual factors. Many patients have the most discomfort early on, with gradual improvement as tissues heal and mobility returns. Pain control strategies and recovery timelines vary by clinician and case.

Q: When can someone walk or put weight on the leg after surgery?
Weight-bearing recommendations depend on fracture stability, fixation quality, and surgeon preference. Some cases allow earlier weight bearing, while others require a period of limited loading to protect healing. This varies by clinician and case.

Q: How long does it take for the fracture to heal?
Bone healing timelines vary depending on fracture type, displacement, patient health, and mechanical stability. Follow-up visits and imaging are used to monitor progress rather than relying on a single universal timeline. Exact duration varies by clinician and case.

Q: Can you drive or return to work with femoral neck screws?
Return to driving and work depends on pain control, mobility, side of surgery, vehicle type, medications, and job demands. Desk-based work may differ from physically demanding work in timing and restrictions. Clearance and timing vary by clinician and case.

Q: Are cannulated screws safe with MRI or airport security?
Many modern orthopedic implants are made from materials commonly used in medical devices, such as titanium alloys or stainless steel. MRI compatibility depends on the specific implant and manufacturer labeling, and security scanners may or may not detect metal hardware. These details vary by material and manufacturer.

Q: What complications are clinicians watching for after femoral neck fixation?
Follow-up commonly focuses on fracture healing, maintenance of alignment, and hardware position. Clinicians may also monitor for issues such as delayed union/nonunion, hardware failure, infection, and femoral head blood-supply problems that can occur after femoral neck fractures. The likelihood of specific complications varies by clinician and case.