Views: 0 Author: Site Editor Publish Time: 2026-08-14 Origin: Site
Introduction
Femoral neck fractures are commonly treated with internal fixation in younger and physiologically active patients, particularly when preservation of the native femoral head is the treatment goal. Among the available fixation strategies, three parallel cannulated screws arranged in an inverted triangular configuration remain a widely used technique for suitable femoral neck fractures.
After fracture union, however, surgeons may face another clinical question:
Should the cannulated screws be routinely removed?
Some patients develop local irritation, pain, limited function, or psychological discomfort related to the implants. In other cases, implant removal may be considered because of hardware prominence or other implant-related symptoms.
However, removal of a healed femoral neck fracture is not necessarily a risk-free procedure. Concerns include femoral head vascular compromise, femoral neck refracture, changes in proximal femoral stress distribution, and potentially osteonecrosis of the femoral head (ONFH).
Therefore, the decision should not be based simply on whether the fracture has united.
Instead, clinicians should consider the patient's age, fracture characteristics, radiographic healing, symptoms, implant position, femoral head viability, and the potential biomechanical consequences of implant removal.
For many femoral neck fractures in younger patients, internal fixation is intended to achieve stable fracture fixation while preserving the native femoral head.
A commonly used configuration consists of three cannulated screws placed parallel to one another in an inverted triangular pattern.
The configuration typically provides:
Multiple points of fixation
Resistance to rotational displacement
Compression across the fracture site
Support within the femoral neck
Relatively limited surgical exposure
The inferior screw is often positioned close to the calcar femorale, while the other screws are distributed toward the superior aspects of the femoral neck.
This arrangement attempts to optimize both fixation stability and load transfer across the proximal femur.
However, once fracture healing has occurred, these screws become part of the biomechanical environment of the proximal femur.
Removing them therefore changes the local load-bearing pattern.
Not necessarily.
A healed fracture alone does not constitute an absolute indication for implant removal.
In an asymptomatic patient with satisfactory fracture union and no implant-related complications, routine removal may not provide a clear clinical benefit.
This is particularly important in young patients because removal of deeply positioned screws requires another surgical procedure and may potentially alter the structural and vascular environment of the femoral neck.
The decision should therefore be individualized.
Persistent implant-related pain
Symptomatic hardware prominence
Local soft-tissue irritation
Mechanical symptoms
Infection
Implant migration or failure
Patient-specific functional limitations
Strong patient preference after informed discussion of potential risks
The key question is not simply:
“Has the fracture healed?”
but rather:
“Does the expected benefit of implant removal outweigh the potential biological and biomechanical risks?”
One important source of evidence is a meta-analysis evaluating the relationship between internal fixation removal and osteonecrosis of the femoral head after femoral neck fracture in young and middle-aged patients.
The analysis compared patients in whom fixation devices were retained with those in whom the implants were removed after fracture healing.
The results suggested that the implant-removal group had a higher incidence of ONFH than the implant-retention group.
However, this finding requires careful interpretation.
The available clinical studies may contain important confounding factors, including:
Fracture severity
Initial displacement
Reduction quality
Time from injury to fixation
Patient age
Existing vascular injury
Surgical technique
Timing of implant removal
Differences between symptomatic and asymptomatic patients
Therefore, it would be inappropriate to conclude that:
“Removing cannulated screws directly causes femoral head necrosis.”
A more evidence-based interpretation is:
Implant removal after femoral neck fracture union has been associated with an increased risk of ONFH in some clinical analyses, although a direct causal relationship has not been definitively established.
This distinction is particularly important when communicating evidence to clinicians.
The femoral head has a relatively vulnerable blood supply.
The principal vascular contribution in adults comes from branches of the medial femoral circumflex artery, particularly the retinacular vessels.
Femoral neck fractures themselves can disrupt these vessels.
Consequently, a patient who has already sustained vascular injury may have a compromised blood supply before implant removal is even considered.
Additional surgical manipulation around the femoral neck could potentially introduce further biological stress.
This means that ONFH after screw removal may represent a multifactorial process, rather than a simple consequence of removing the metal implant.
Possible contributors include:
Initial vascular injury caused by the fracture
Fracture displacement
Surgical manipulation
Changes in local biomechanics
Repeated surgical trauma
Alteration of stress distribution after implant removal
Therefore, the presence of healed bone does not necessarily mean that the femoral head has completely recovered biologically.
ONFH is not the only potential complication.
Femoral neck refracture is another important concern after implant removal.
Cannulated screws occupy relatively small channels within the femoral neck and proximal femur. Once they are removed, these screw tracks temporarily represent areas of reduced structural continuity.
The resulting effect depends on:
Screw diameter
Screw position
Number of screws
Bone quality
Residual screw holes
Femoral neck geometry
Loading conditions
Time since fracture union
In younger patients with good bone quality, the absolute risk may be different from that in elderly patients with osteoporosis.
Nevertheless, immediately after screw removal, the proximal femur may not have the same mechanical behavior as an intact femur.
This is why postoperative weight-bearing management deserves particular attention.
Biomechanical studies provide another perspective.
Finite element analysis has been used to investigate changes in stress distribution after removal of cannulated screws from a healed femoral neck fracture.
In a representative computational model, researchers compared the mechanical behavior of the proximal femur before and after screw removal.
The analysis suggested that implant removal could produce:
Increased local stress concentration
Altered load transfer through the femoral neck
Increased average stress within portions of the femoral head and neck
A potentially greater mechanical demand on the remaining bone
Importantly, these findings should be interpreted as biomechanical evidence, not direct clinical proof.
Finite element models can demonstrate how stress and strain may change, but they cannot independently establish that a particular screw-removal sequence prevents ONFH or refracture in real patients.
One interesting finding from biomechanical research concerns the sequence of screw removal.
In the analyzed model, removing the inferior screw closest to the calcar first produced the smallest change in proximal femoral stress concentration and femoral-head stress compared with other removal sequences.
Based on this biomechanical model, the authors proposed a staged strategy:
First remove the inferior screw near the calcar.
The remaining two screws are then retained temporarily rather than being removed simultaneously.
After an interval of approximately four months, the remaining two screws can be considered for removal.
This approach is intended to allow gradual adaptation of the proximal femur to the changing load environment.
However, this should be viewed as a biomechanical proposal rather than a universally established clinical protocol.
Further clinical studies would be required to determine whether this strategy actually reduces refracture or ONFH rates.
The biomechanical rationale behind staged removal is relatively straightforward.
If three screws are removed simultaneously, the proximal femur loses all three internal fixation elements at once.
This may produce a relatively abrupt change in mechanical load transfer.
By contrast, sequential removal allows the remaining implants to continue sharing part of the load during the initial adaptation period.
Conceptually:
Three screws → remove one → temporary load sharing by two screws → bone remodeling/adaptation → remove remaining screws
This may reduce the magnitude of the immediate mechanical transition.
Again, however, the exact timing should not be regarded as universally applicable to every patient.
Caution with weight bearing is reasonable.
Following implant removal, the screw channels remain within the proximal femur.
The mechanical environment therefore differs from that of an intact femur.
Particularly in patients with:
Poor bone quality
Large screw diameters
Multiple previous surgeries
Persistent femoral neck deformity
Marginal fracture healing
Previous complications
High physical activity levels
immediate unrestricted loading may not be appropriate.
The postoperative rehabilitation protocol should be individualized according to:
Radiographic evidence of union
Bone quality
Femoral neck morphology
Screw-hole characteristics
Intraoperative findings
Patient age and activity level
Where there is concern about structural weakness, temporary protection from full weight bearing may be considered.
A practical decision-making framework can be divided into four steps.
Before considering removal, evaluate:
Bridging trabeculae
Disappearance of the fracture line
Absence of progressive displacement
Stable implant position
Clinical absence of fracture-related pain
Additional imaging may be considered when conventional radiographs are inconclusive.
Because ONFH is an important complication after femoral neck fracture, the biological status of the femoral head should be considered.
Depending on the clinical situation, assessment may include:
Serial radiographs
MRI
Clinical symptoms
Evidence of femoral-head collapse
Patients with unexplained hip pain or radiographic abnormalities may require further evaluation before elective implant removal.
The presence of metal alone is not necessarily an indication.
The surgeon should determine whether the patient has:
Symptomatic hardware
Implant-related irritation
Mechanical problems
Infection
Implant failure
Another clearly defined indication
For an asymptomatic patient, observation may be a reasonable alternative.
Shared decision-making is particularly important in young patients.
The discussion should include the potential benefits of removal as well as possible complications, including:
Infection
Neurovascular injury
Femoral neck fracture
Refracture
Altered proximal femoral biomechanics
Potential risk of ONFH
Need for additional surgery
The patient should understand that removing a healed implant does not necessarily restore the femur to its original biomechanical condition immediately.
When implant removal is indicated, the basic surgical principle is to reproduce the original screw trajectory whenever possible.
Under fluoroscopic guidance, the surgeon identifies the screw heads and confirms their location.
Soft-tissue dissection should be minimized.
The previous incision or a limited approach may be used when appropriate.
Care should be taken to avoid unnecessary soft-tissue injury.
The appropriate cannulated screwdriver should fully engage the screw recess.
A damaged screw head can make removal significantly more difficult.
When staged removal is selected, the planned sequence should be followed.
Based on the finite element analysis discussed above, the inferior/calcar screw was proposed as the first screw for removal, followed by delayed removal of the remaining screws.
Fluoroscopy can confirm that:
All intended implants have been removed
No screw fragments remain
No new fracture has occurred
Because the mechanical environment has changed, postoperative weight-bearing restrictions should be determined according to the patient's structural and biological status.
There is no universal rule requiring simultaneous removal.
For an asymptomatic patient, the question of whether removal is necessary should be addressed first.
If removal is indicated, staged removal may be considered in selected cases, particularly when biomechanical concerns are substantial.
The proposed staged approach is:
First operation: remove the inferior screw near the calcar.
Adaptation period: maintain the remaining two screws.
Approximately four months later: reassess the proximal femur and consider removal of the remaining screws if clinically appropriate.
However, this strategy is based primarily on biomechanical modeling and should not be presented as an established evidence-based standard for all patients.
The inferior screw is usually positioned close to the calcar femorale, an important load-bearing region of the proximal femur.
Its position allows it to participate in load transfer through the femoral neck.
Removing this screw therefore changes the mechanical environment.
Interestingly, finite element analysis suggested that removing the inferior screw first generated the smallest overall increase in stress concentration in the modeled femur.
This seemingly counterintuitive result highlights an important point:
The safest removal sequence cannot necessarily be determined simply by considering which screw carries the greatest load.
The entire three-dimensional stress distribution needs to be considered.
This distinction is essential when interpreting the available literature.
| Evidence type | What it can tell us | Main limitation |
|---|---|---|
| Meta-analysis | Association between implant removal and clinical outcomes | Confounding and heterogeneity |
| Clinical case reports | Possible complications and clinical patterns | Cannot establish causation |
| Finite element analysis | Stress and load redistribution | Does not directly predict clinical outcomes |
| Radiographic studies | Fracture union and structural changes | Limited information on biological viability |
| MRI | Femoral-head and marrow changes | Availability and interpretation limitations |
Therefore, no single study should be used to establish a universal implant-removal protocol.
A simple clinical framework can be summarized as follows:
→ Routine removal is not necessarily required.
→ Consider removal after evaluating the indication and potential risks.
→ Evaluate the femoral head before elective implant removal.
→ Consider whether retention or staged removal is safer.
→ Consider a minimally invasive approach, appropriate screw-removal technique, postoperative protection, and individualized rehabilitation.
The most important lessons are not simply about how to remove a cannulated screw, but whether it should be removed at all.
Fracture union alone is not an automatic indication for implant removal.
Clinical evidence has suggested an association between implant removal and increased ONFH incidence, but causality has not been definitively established.
Femoral head vascular status should be considered before elective implant removal.
Removal changes the mechanical environment of the proximal femur.
Femoral neck refracture is another important potential complication.
Finite element analysis suggests that staged removal may produce a more gradual biomechanical transition.
The inferior screw near the calcar has been proposed as the first screw for removal in one biomechanical model.
The remaining screws may be retained temporarily before subsequent removal in selected cases.
Immediate unrestricted weight bearing after implant removal should not automatically be assumed to be safe.
The decision should ultimately be individualized through shared decision-making.
No. Routine removal is not necessarily required in an asymptomatic patient with satisfactory fracture union and stable implants.
Available clinical evidence suggests an association between implant removal and a higher incidence of ONFH in some patient populations. However, this does not prove that screw removal itself directly causes ONFH.
Yes. Removal creates screw channels and changes the mechanical environment of the proximal femur. Refracture is therefore an important potential complication.
A finite element study proposed removing the inferior screw near the calcar first because this produced the smallest stress changes in the modeled proximal femur. However, this is biomechanical evidence rather than a universally accepted clinical guideline.
Not necessarily. In selected patients, staged removal may be considered. The decision should depend on the clinical indication, bone quality, fracture characteristics, and surgeon assessment.
One biomechanical study proposed an interval of approximately four months before removing the remaining two screws. This should be regarded as a study-derived strategy rather than a universally established clinical recommendation.
Not necessarily. Weight-bearing should be individualized according to bone quality, femoral neck structure, screw-hole characteristics, and the patient's overall risk profile.
Cannulated screw removal after healed femoral neck fracture should be regarded as an individualized clinical decision rather than a routine postoperative step.
Although some patients may benefit from implant removal because of pain, irritation, mechanical symptoms, infection, or other implant-related problems, removal can also alter the biological and biomechanical environment of the proximal femur.
Clinical evidence has raised concerns regarding a possible association between implant removal and osteonecrosis of the femoral head, while biomechanical studies suggest that screw removal may increase local stress concentration and potentially influence refracture risk.
For patients in whom removal is indicated, careful preoperative assessment, appropriate surgical technique, consideration of staged removal, and postoperative protection of the proximal femur may be important.
Ultimately, the most appropriate strategy is not simply:
“The fracture has healed, so remove the screws.”
Instead, the decision should be based on a more fundamental question:
“For this particular patient, does the expected benefit of implant removal outweigh its biological and biomechanical risks?”
For orthopedic surgeons and medical device distributors, appropriate instrumentation is an important part of safe and efficient implant removal procedures.
Toolmed provides orthopedic trauma instruments and implant systems designed for procedures involving fracture fixation, implant removal, and orthopedic trauma surgery.
Our product portfolio includes:
Cannulated screw instruments
Cannulated screwdrivers
Guide wires and guide pins
Orthopedic extraction instruments
Trauma instrument sets
Femoral neck fracture fixation systems
Cannulated screw fixation systems
Orthopedic implant removal instruments
For hospitals, orthopedic distributors, and medical device companies looking for orthopedic trauma instruments and cannulated screw fixation solutions, Toolmed can provide product information, instrument configurations, and OEM/ODM support.
Contact Toolmed to discuss your orthopedic trauma instrument requirements.
Cheng EY, et al. Management of Nontraumatic Osteonecrosis of the Femoral Head: An International Evidence-Based Clinical Practice Guideline. Journal of Bone and Joint Surgery. 2026.
Relevant systematic reviews and meta-analyses evaluating the association between internal fixation removal and osteonecrosis after femoral neck fracture in young and middle-aged patients.
Biomechanical and finite element studies investigating stress redistribution and screw-removal sequences after healed femoral neck fracture.
Literature concerning the vascular anatomy of the femoral head and the pathogenesis of osteonecrosis following femoral neck fracture.
Literature concerning femoral neck refracture and biomechanical changes following removal of internal fixation devices.
Editorial note: The clinical recommendations above distinguish between clinical evidence, biomechanical modeling, and expert interpretation. The proposed sequence of removing the inferior screw first and delaying removal of the remaining screws should be regarded as a biomechanical-study-derived strategy, not as a universally established surgical guideline.
