Dynamic hip screw: Definition, Uses, and Clinical Overview

Dynamic hip screw Introduction (What it is)

Dynamic hip screw is a metal implant used to stabilize certain hip fractures.
It is most commonly used for fractures near the top of the thigh bone (proximal femur).
It combines a large “sliding” screw with a side plate that attaches to the femur.
Its design allows controlled compression at the fracture while maintaining alignment.

Why Dynamic hip screw used (Purpose / benefits)

A Dynamic hip screw is used to repair specific fractures of the proximal femur, especially fractures around the trochanteric region (the bony prominences near the hip). The main problem it addresses is mechanical instability: when the upper femur breaks, the bone fragments can shift, collapse, or rotate, making standing and walking difficult and potentially preventing the bone from healing in a good position.

The “dynamic” part of the design refers to controlled sliding of the main screw within a barrel on the side plate. As the patient bears weight (when permitted), the fracture can compress in a controlled way, which may support bone healing. In simple terms, it is intended to hold the broken bone still enough to heal, while allowing a small amount of purposeful settling at the fracture site rather than forcing the bone to remain rigidly separated.

Potential benefits clinicians consider include:

• Internal stability for healing: provides fixation to keep bone fragments aligned.
• Controlled impaction/compression: sliding mechanism can encourage fracture contact.
• Familiar, widely taught construct: commonly used in orthopedic trauma settings.
• Modular sizing: available in different lengths, angles, and configurations.
• Compatibility with intraoperative imaging: placement is typically checked using X-ray imaging during surgery.

The choice to use a Dynamic hip screw depends on fracture pattern, bone quality, patient factors, and surgeon preference. Outcomes and protocols vary by clinician and case.

Indications (When orthopedic clinicians use it)

Typical scenarios where a Dynamic hip screw may be considered include:

• Stable intertrochanteric (pertrochanteric) fractures of the proximal femur
• Some basicervical fracture patterns (near the base of the femoral neck), depending on stability and surgeon judgment
• Proximal femur fractures where controlled sliding compression is desired
• Cases where the lateral femoral cortex provides adequate support for a plate-based construct
• Situations where an intramedullary device is not preferred or not feasible due to anatomy or other factors (varies by clinician and case)

Contraindications / when it’s NOT ideal

A Dynamic hip screw is not suitable for every hip fracture. Situations where it may be less ideal or where another approach may be chosen include:

• Unstable intertrochanteric patterns (for example, patterns prone to medial or lateral wall failure), where a different fixation strategy may better control collapse and rotation
• Reverse obliquity or fracture lines that tend to displace under load, where intramedullary fixation is often considered
• Subtrochanteric fractures (below the trochanters), which frequently require different biomechanics than a sliding hip screw provides
• Severely comminuted fractures (many fragments) with poor structural support for a plate-and-screw construct
• Advanced pre-existing hip arthritis or femoral head damage where arthroplasty (joint replacement) may be considered instead of fixation (varies by clinician and case)
• Certain pathologic fractures (due to tumors or metabolic bone disease), where fixation choice depends on diagnosis, bone quality, and expected healing
• Infection at or near the surgical site or other systemic issues that may change timing or implant choice (managed case-by-case)

“Not ideal” does not mean “never used.” It means the risk–benefit balance may favor a different device or operation depending on fracture mechanics and patient factors.

How it works (Mechanism / physiology)

Biomechanical principle: controlled sliding compression

A Dynamic hip screw works by anchoring a large screw (often called a lag screw) into the femoral head and neck while connecting that screw to a side plate fixed along the outer (lateral) femur. The key feature is that the lag screw can slide within the plate’s barrel. This allows the fracture to compress as the patient loads the limb (when allowed), bringing bone surfaces into contact.

This controlled collapse can be desirable in selected fracture patterns because bone healing generally benefits from stable contact and appropriate compression. However, too much collapse can affect leg length or hip mechanics, which is one reason fracture selection and technique matter.

Relevant hip anatomy (simplified)

• Femoral head: the “ball” that sits in the hip socket.
• Femoral neck: the narrowed bridge connecting head to shaft.
• Intertrochanteric region: the area between the greater and lesser trochanters; a common site of hip fractures in older adults.
• Femoral shaft (proximal): the upper segment of the thigh bone where the plate is anchored.

The implant does not heal the bone directly. Instead, it stabilizes alignment and load-sharing so the body can form new bone across the fracture.

Onset, duration, and reversibility (what applies here)

• Onset: mechanical stabilization is immediate once implanted, but bone healing takes time and varies by individual and fracture type.
• Duration: the implant is designed to remain in place long term unless there is a complication or a specific reason for removal.
• Reversibility: it can be surgically removed, but removal is not automatically required and depends on symptoms, healing, and clinician judgment.

Dynamic hip screw Procedure overview (How it’s applied)

Dynamic hip screw is an implant, and it is placed during an orthopedic fracture fixation surgery. A simplified, high-level workflow often looks like this:

1. Evaluation / exam
   – History, physical exam, and assessment of function and pain
   – Imaging, typically X-rays; CT may be used in selected cases (varies by clinician and case)
   – Assessment of fracture pattern, bone quality, and overall medical status

2. Preparation
   – Surgical planning (implant sizing, plate angle, screw length)
   – Anesthesia planning and medical optimization as appropriate
   – Positioning to allow fracture alignment and imaging during the procedure

3. Intervention (implant placement)
   – Fracture reduction (bringing bone fragments into improved alignment)
   – Guidewire placement into the femoral head/neck under imaging
   – Reaming and insertion of the lag screw
   – Attachment of the side plate to the femoral shaft with additional screws
   – Optional add-ons in selected patterns (for example, trochanteric stabilization components)

4. Immediate checks
   – Imaging to confirm alignment and implant position
   – Stability assessment and closure of soft tissues

5. Follow-up
   – Scheduled visits with repeat imaging to monitor healing
   – A rehabilitation plan tailored to the fracture stability, patient health, and surgeon protocol
   – Progression of activity and weight-bearing status varies by clinician and case

This overview is intentionally general; exact steps and protocols depend on the fracture and the surgical team.

Types / variations

A Dynamic hip screw system can vary in design and configuration. Common variations include:

• Plate angle options
  Side plates come in different fixed angles to match patient anatomy and fracture needs (specific angles vary by manufacturer).

• Plate length (number of holes)
  Plates may be shorter or longer depending on how many screws are used to anchor to the femoral shaft and how the fracture is distributed.

• Barrel length (short vs long barrel)
  The barrel guides the sliding of the lag screw; barrel length selection depends on implant system design and surgeon preference.

• Materials and coatings
  Common orthopedic implant materials include stainless steel and titanium alloys; exact properties vary by material and manufacturer.

• Augmented constructs
  In selected unstable patterns, surgeons may add a trochanteric stabilization plate or other adjuncts to better control lateral wall issues and fragment migration (used selectively; varies by clinician and case).

• Supplemental anti-rotation strategies
  Some techniques use additional measures to reduce femoral head/neck rotation during healing. Whether this is used depends on fracture pattern and implant system.

Pros and cons

Pros:

• Allows controlled compression at the fracture site through its sliding mechanism
• Widely recognized option for selected intertrochanteric fractures
• Modular system with multiple sizes and configurations
• Fixation is internal, so there is no external frame or pins outside the skin
• Intraoperative imaging helps confirm alignment and hardware position
• Can be compatible with a range of rehabilitation approaches (details vary by case)

Cons:

• Not ideal for all fracture patterns, especially some unstable or subtrochanteric configurations
• Risk of mechanical complications such as excessive collapse or loss of alignment in unsuitable patterns
• Implant-related issues can occur (for example, screw cut-out, breakage, or loosening), with risk influenced by bone quality, fracture stability, and placement
• Requires surgery and anesthesia, which carry general procedural risks
• Postoperative function and recovery can be limited by pre-injury health, muscle strength, and comorbidities
• Some patients may feel hardware irritation, though symptoms vary and are not universal

Aftercare & longevity

Aftercare following fixation with a Dynamic hip screw typically focuses on protecting the repair while supporting safe mobility and functional recovery. What this looks like can differ substantially, so clinicians individualize plans.

Key factors that commonly affect outcomes and longevity include:

• Fracture pattern and stability: stable fractures generally tolerate the sliding/compression concept better than unstable patterns.
• Quality of reduction and implant position: alignment and positioning are assessed with imaging; small differences can influence mechanics.
• Bone quality: osteoporosis or poor bone stock can reduce purchase (grip) of screws and affect fixation reliability.
• Weight-bearing status and progression: restrictions and timelines vary by clinician and case and may change based on healing seen on follow-up imaging.
• Rehabilitation participation: restoring hip strength, balance, and gait mechanics is often part of recovery, but specific exercises and milestones are individualized.
• Medical comorbidities and nutrition: overall health can influence healing capacity and complication risk.
• Device choice and construct details: plate length, screw sizing, and adjunct stabilization can change mechanical behavior.

Longevity of the implant is often long term. Some people live with the hardware indefinitely, while others may require additional procedures if complications occur or if the clinical situation changes. Whether removal is considered depends on healing, symptoms, and clinician judgment.

Alternatives / comparisons

Dynamic hip screw is one of several ways to manage proximal femur fractures, and it is typically chosen based on fracture mechanics and patient context.

Common alternatives include:

• Cephalomedullary nail (intramedullary hip nail)
  This is a rod placed inside the femoral canal with a screw or blade into the femoral head. It is often considered for certain unstable intertrochanteric patterns and subtrochanteric fractures because it can offer different load-sharing mechanics. Choice versus Dynamic hip screw varies by clinician and case.

• Multiple cannulated screws (percutaneous screw fixation)
  Often discussed for selected femoral neck fractures rather than typical intertrochanteric fractures. It can be less invasive in some contexts but may not provide the same controlled sliding compression used for pertrochanteric patterns.

• Arthroplasty (hemiarthroplasty or total hip replacement)
  For some fractures—especially certain displaced femoral neck fractures or cases with poor femoral head viability—replacement may be chosen instead of fixation. This changes the goal from bone healing across the fracture to restoring function through an artificial joint.

• Nonoperative management (observation, pain control, and supportive care)
  In patients who are not surgical candidates or in limited scenarios, nonoperative pathways may be used. These approaches trade surgical stabilization for supportive management and may carry different risks related to mobility and fracture healing.

• External fixation (less common for typical hip fractures)
  Used in select trauma situations or as a temporary measure in complex cases; not a standard choice for most intertrochanteric fractures.

A balanced comparison is that Dynamic hip screw is a well-established option for certain fracture types, while nails or arthroplasty may better match other patterns or patient needs. The “right” choice is individualized and depends on anatomy, stability, and overall goals of care.

Dynamic hip screw Common questions (FAQ)

Q: Is a Dynamic hip screw the same thing as a hip replacement?
No. A Dynamic hip screw is a fixation device used to hold a broken bone in position so it can heal. A hip replacement removes and replaces joint surfaces with artificial components, which is a different operation with different indications.

Q: Will I have pain after surgery with a Dynamic hip screw?
Postoperative pain is common after fracture fixation, especially in the early period. Pain sources can include the fracture itself, soft tissue healing, and muscle weakness. The type and duration of pain vary by clinician and case.

Q: How long does a Dynamic hip screw last inside the body?
It is designed to be durable and often remains in place long term. Some patients never need hardware removed, while others may require additional surgery if there are complications or persistent symptoms. Long-term course depends on healing, implant position, and individual factors.

Q: Does the Dynamic hip screw need to be removed later?
Not routinely. Hardware removal is typically considered only if there is a specific clinical reason, such as symptoms felt to be related to the implant, infection, or mechanical failure. Decisions about removal vary by clinician and case.

Q: When can someone walk or put weight on the leg after this surgery?
Weight-bearing plans depend on fracture stability, bone quality, implant configuration, and the surgeon’s assessment. Some patients may be allowed earlier weight bearing, while others may need restrictions. The timeline varies by clinician and case.

Q: How soon can a person drive or return to work after Dynamic hip screw fixation?
Driving and work timing depends on pain control, mobility, reaction time, side of surgery, and whether assistive devices are still needed. Return-to-work timelines also depend on job demands (desk work versus physically demanding work). Clinicians typically individualize recommendations based on function and safety considerations.

Q: What are the main risks or complications of a Dynamic hip screw?
Potential issues include infection, blood clots, anesthesia-related risks, and mechanical complications such as loss of fixation or screw migration. The likelihood of specific complications depends on fracture type, bone quality, and surgical technique. Monitoring with follow-up visits and imaging is used to assess healing and hardware position.

Q: Will the metal set off airport security or affect daily life?
Implants can sometimes trigger metal detectors, though this is inconsistent. In daily life, many people do not notice the implant once healing and rehabilitation progress. Sensations around the incision or with certain activities can occur and vary between individuals.

Q: Can someone get an MRI with a Dynamic hip screw?
Many orthopedic implants are MRI compatible under specific conditions, but compatibility depends on the exact implant material and manufacturer. Imaging centers typically verify the implant type before scanning. If MRI is needed, clinicians and radiology teams confirm safety details.

Q: Does a Dynamic hip screw “compress” the fracture on purpose?
Yes, in a controlled way. The sliding mechanism can allow the fracture to settle and compress as load is applied, which may support healing in selected patterns. Too much collapse can be a concern in some fractures, which is why patient selection and technique matter.