Indications and techniques of proximal femoral osteotomies in 2026

Authors: Samuel Friedrich Schaible, Paulo Rego, Simon Damian Steppacher, Sjard Simons, Moritz Tannast

Abstract

Proximal femoral osteotomy remains an important joint-preserving option for adolescents and young adults with symptomatic proximal femoral deformity, preserved cartilage, and deformity amenable to correction.Surgical hip dislocation provides circumferential access to the femoral head, neck, and acetabulum while preserving the retinacular blood supply, and it allows direct dynamic assessment of impingement together with concomitant treatment of intra-articular pathology.The extended retinacular flap has expanded the indications for intra-articular correction at the femoral neck and head level, enabling larger corrections closer to the deformity with less secondary displacement when compared to extra-articular osteotomies.Preoperative planning must combine standardized radiographs, CT- or MRI-based torsion analysis, and MRI-based cartilage assessment; outcomes depend mainly on cartilage status, patient age, timing of correction, and technical precision.

Introduction

In the absence of advanced osteoarthritis, proximal femoral osteotomy remains a valuable surgical option for young patients because it addresses the structural source of abnormal joint mechanics before irreversible cartilage damage occurs. This concept has gained importance as femoroacetabular impingement, instability, and femoral torsion have become better understood and can be treated in a deformity-specific way (Table 1) (1, 2).

Historically, extra-articular intertrochanteric and subtrochanteric osteotomies were the primary surgical tools for addressing femoral deformities, moderate osteoarthritis, nonunion, and avascular necrosis (3). Their long-term outcomes were variable, with reported ten-year survival rates ranging from 50 to 89% depending on the indication and the series (4). Their limitations were not only the inability to address concomitant intra-articular pathology directly\ but also the geometry of correction because the osteotomy was performed away from the center of deformity, angular correction inevitably translated the femoral shaft, altered abductor mechanics, and could create secondary impingement or changes in lower-limb mechanics (1, 2). Varus intertrochanteric osteotomy, for example, could lead to abductor weakness and secondary extra-articular impingement, whereas angular correction at the intertrochanteric level inevitably medialized or lateralized the femoral shaft and altered the mechanical axis of the limb (1, 2). Total hip arthroplasty after previous femoral osteotomy is also technically more demanding and may carry a higher complication risk (5).

The modern era of proximal femoral osteotomy was shaped by two better understanding of femoral head perfusion through the medial femoral circumflex artery (6, 7), and the introduction of surgical hip dislocation as a reproducible approach that provides full access to the joint without compromising the retinacular blood supply (8). The low complication rate of surgical hip dislocation allowed routine combination of osteotomy with treatment of intra-articular pathology and direct intraoperative assessment of the actual impingement pattern (9). Trochanteric advancement could be used to address abductor insufficiency and extra-articular impingement, and the extended retinacular flap made femoral neck and femoral head osteotomies possible closer to the deformity itself (10), allowing larger corrections with less secondary angulation and less limb-length change than extra-articular procedures (11).

In practice, proximal femoral osteotomy is most suitable for adolescents and young adults with preserved cartilage, a correctable deformity, and sufficient bone quality for stable fixation (1, 12). This review summarizes current indications and key techniques according to osteotomy level, ranging from subtrochanteric to intra-articular procedures.

Preoperative imaging

Imaging assessment is fundamental to patient selection and surgical planning. Radiographic evaluation begins with a standardized anteroposterior pelvis radiograph, supplemented by lateral projections such as the cross-table lateral view to characterize femoral head coverage and the head–neck junction in multiple planes (13). Functional radiographs in abduction and adduction are valuable because they simulate the congruency achievable through osteotomy and help distinguish structural loss of congruency from dynamic instability (2, 13). Relevant parameters include acetabular coverage, the neck–shaft angle, the alpha angle at the head–neck junction, and femoral head–neck offset (13, 14). Full-length standing films are required when limb-length discrepancy or mechanical axis deviation is suspected, as proximal femoral correction can influence knee alignment.

Computed tomography remains the reference standard for quantifying femoral torsion, although MRI can provide comparable measurements when the protocol includes the proximal femur and distal femoral condyles, thereby avoiding radiation exposure in younger patients (15, 16, 17). The Murphy method, which relates the femoral head–neck axis to the posterior condylar axis, most closely reflects true anatomical torsion (16). Modern low-dose protocols reduce radiation exposure (18). Three-dimensional CT datasets are also useful for impingement analysis, virtual range-of-motion simulation, and patient-specific instrumentation in complex cases (19).

Magnetic resonance imaging is the gold-standard cross-sectional modality for soft tissue evaluation in hip preservation. Assessment of the labrum and, especially, articular cartilage is critical for deciding whether osteotomy remains reasonable or arthroplasty is more appropriate (20). Radial sequences aligned with the femoral neck improve the assessment of cam deformity and labral pathology (21). In selected cases, traction MR arthrography can improve visualization of labral and cartilage lesions and may also assist in risk stratification, as extensive acetabular cartilage damage, central femoral osteophytes, and combined femoral cartilage and ligamentum teres damage were independently associated with failure after FAI surgery in a recent clinical series (22). Quantitative compositional techniques such as delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) can provide adjunctive information on cartilage quality and refine joint-preservation decision-making (16, 23).

Clinical examination

Clinical examination generates the initial diagnostic hypothesis and guides the imaging work-up. Gait analysis can reveal torsional clues such as in-toeing, which often accompanies increased femoral antetorsion, or out-toeing, which more often accompanies decreased antetorsion or retrotorsion. Normal foot progression does not exclude torsional abnormality because compensation is common (24).

Hip rotation should be assessed with the hip in extension and flexion to 90°. Increased internal rotation suggests excessive antetorsion, whereas increased external rotation suggests retrotorsion, but clinical estimation alone is not precise enough for surgical planning (25). Specific provocative tests, particularly the flexion–adduction–internal rotation (FADIR) test, are highly sensitive for labral lesions but not very specific for the underlying intra- or extra-articular pathology (26). With excessive femoral torsion, painful combined flexion–abduction–internal rotation (FABER) test is suggestive for an ischiofemoral impingement.

In trochanteric pathology, a painful limitation of abduction and extension, especially when provoked in the combined position, is characteristic. Generalized hypermobility, quantified with the Beighton score, should be documented preoperatively because it influences stability and rehabilitation. Examination of spine mobility completes the assessment.

Clinical examination raises suspicion and focuses the workup; deformity definition and operative planning depend on imaging.

Surgical hip dislocation

Surgical hip dislocation provides 360° access to the femoral head, neck, and acetabulum while preserving the retinacular blood supply to the femoral head (8). It is the standard approach for most proximal femoral osteotomies when concomitant intra-articular treatment is required. Because the hip can be repeatedly reduced and taken through provocative motion, it also allows direct visualization and dynamic testing of impingement before and after correction, which is often decisive in confirming whether a proximal femoral correction is indicated and whether the correction is adequate (8, 27).

The key anatomical principle is the preservation of the deep branch of the medial femoral circumflex artery, which runs posterior to the obturator externus tendon and anterior to the conjoined tendon of the gemelli and obturator internus and enters the capsule, giving rise to the lateral retinacular vessels that perfuse the epiphysis (6). These posterosuperior retinacular vessels provide the dominant blood supply in most hips; in the cadaveric study of Kalhor et al., posteriorly approaching vessels dominated femoral head perfusion in 18 of 20 specimens (7).

The patient is positioned in lateral decubitus on a radiolucent table. A lateral skin incision is made, centered over the greater trochanter tip, the iliotibial band is split longitudinally, and the Gibson interval between gluteus maximus and gluteus medius is developed (28). The posterior border of gluteus medius is exposed to the piriformis tendon, which is the safety landmark. Dissection distal to the piriformis near the short external rotators risks injury to the deep branch of the medial femoral circumflex artery and should be avoided (6).

After identification of the trochanteric branch, the most posterior fibers of gluteus medius at the proximal end of the osteotomy are deliberately left intact as a safety bridge for the retinacular vessels, and a trochanteric osteotomy is then performed parallel to the trochanteric surface, creating a fragment 1–1.5 cm thick carrying gluteus medius and vastus lateralis tendons. If anatomic refixation without transfer is planned, a stepped Z-shaped osteotomy increases stability and cancellous contact area and reduces the risk of trochanteric nonunion (29). The posterior trochanter with the piriformis attachment remains on the femur.

The interval between gluteus minimus and piriformis is developed. Capsulotomy begins as a longitudinal incision at the mid-neck level, medial to the anterior retinacular vessels, and is extended distally and cranially to the acetabular rim under labral protection. The femoral head is then subluxated anteriorly with a bone hook on the femoral neck combined with flexion and external rotation; the ligamentum teres is divided in the subluxated position. This allows for a complete inspection of the femoral and acetabular cartilage surfaces (Fig. 1).

Extended retinacular flap

The extended retinacular flap is the key adjunct when correction must be performed at the femoral neck or femoral head level. Through surgical hip dislocation, the posterosuperior retinaculum, periosteum, and capsule are elevated subperiosteally from the femoral neck as a continuous vascularized sleeve, preserving the terminal branches of the medial femoral circumflex artery while allowing controlled mobilization of the epiphysis or head–neck fragment (10). This extension makes true femoral neck osteotomy and femoral head reduction osteotomy possible closer to the deformity itself, but it requires meticulous handling because excessive tension or kinking, particularly after valgus correction, can jeopardize perfusion (10).

Capsule closure should be tension-free to avoid compression of the retinacular vessels (30). The trochanter fragment is refixed with two or three parallel 3.5 or 4.5 mm fully threaded screws countersunk flush to the lateral trochanter. Femoral head perfusion should be confirmed intraoperatively by drill-hole bleeding or laser Doppler flowmetry (30) (Fig. 2).

Extensions

There are useful extensions of the technique. When periacetabular osteotomy is required concurrently for dysplasia or acetabular retroversion, the ischial osteotomy can be performed safely in the lateral position through the interval between quadratus femoris and the triceps coxae under direct protection and vision of the sciatic nerve. After the femoral correction, the patient is turned supine for the remaining pelvic osteotomies and reorientation (2).

Subtrochanteric osteotomy

Indication

Subtrochanteric osteotomy addresses isolated symptomatic femoral torsional abnormality most commonly located in the diaphysis. The main indication is excessive antetorsion or retrotorsion with a consistent clinical pattern, abnormal rotation profile, positive impingement or instability findings, and imaging confirmation. Thresholds such as antetorsion greater than 40° or retrotorsion below 0° are useful guides when the measurement method is specified, but torsion thresholds should be interpreted in relation to the pelvic morphology (16). The definitive amount of correction is determined intraoperatively by restoration of impingement-free motion and stability but should not exceed ±20° as larger corrections may exceed the adaptive capacity of the surrounding musculature or patellar tracking (31, 32). Retrotorsion may be post-traumatic or part of Perthes sequelae. The subtrochanteric level is also useful when a femoral neck procedure is planned concurrently because it avoids implant conflict around the trochanter (29). Multiplanar deformities with relevant varus–valgus or flexion–extension components are better addressed at the intertrochanteric level because that osteotomy is closer to the proximal deformity, more suitable for combined angular and rotational correction, and located in metaphyseal cancellous bone that typically heals faster than a cortical subtrochanteric cut (29, 31). Advanced osteoarthritis and poor bone quality are contraindications.

Technique

After any intracapsular step has been completed through surgical hip dislocation, the femoral shaft is exposed distal to the lesser trochanter. An epiperiosteal approach is preferred. Torsional correction is controlled with two 2.5 mm Kirschner wires used as rotation references, one in the proximal fragment and one in the distal fragment. They are inserted at an angle corresponding to the planned correction, using metallic angle templates for reproducibility. The osteotomy is performed as a transverse cut perpendicular to the femoral shaft. The distal fragment is then rotated until the reference wires are parallel in the axial plane, confirming the intended correction. In lateral decubitus, moving the leg downward externally rotates the distal fragment, decreasing torsion, whereas moving it upward internally rotates it, increasing it. Fixation is achieved with a lateral 4.5/5.0 mm LCP compression plate and eccentric screw placement distal to the osteotomy to create compression. Typical corrections range from 15 to 20°. Larger corrections, particularly in derotational osteotomies, should be performed with caution and may be combined with additional varization to achieve lateralization of the femur. However, every 10° of subtrochanteric rotation shifts the greater trochanter by roughly 1 cm in the anteroposterior plane and measurably changes the abductor lever arm, so large corrections require careful planning of residual impingement and abductor mechanics (31, 32, 33), potentially requiring trochanteric advancement. Because healing at the subtrochanteric level is slower than in cancellous intertrochanteric bone, smoking and premature weight bearing increase the risk of nonunion (31, 34) (Figs 3 and 4).

Intertrochanteric osteotomy

Indication

Intertrochanteric osteotomy remains the main option for multiplanar correction of proximal femoral deformity. It can address coronal, sagittal, and rotational malalignment in one procedure. In the coronal plane, valgization is indicated for coxa vara, post-traumatic varus deformity, and femoral neck pseudarthrosis because it reorients an oblique nonunion or deformity line toward a more horizontal configuration, thereby reducing shear and increasing the compressive component of the joint reaction force across the femoral neck (1, 34, 35). Selected partial avascular necrosis may also benefit from valgization to unload the necrotic segment. Varization is used for coxa valga, to improve coverage in mild dysplasia, and to improve congruency in Perthes deformity or fovea alta; more severe dysplasia requires concurrent acetabular reorientation.

In the sagittal plane, flexion and extension osteotomies have become uncommon and are now mainly reserved as an adjunct for cases of focal avascular necrosis to reposition the remaining intact cartilage into the weight-bearing zone (1). Classic combined intertrochanteric osteotomies for post-slip deformities, such as the Imhäuser osteotomy (36), have largely lost their relevance and are better addressed at the level of the deformity, typically at the femoral neck. Approximate correction limits are 25° in the coronal plane, 30° of flexion, 15° of extension, and 30° of rotation in each direction (34, 35). Beyond roughly 25° of coronal correction, the greater trochanter is displaced enough that an additional trochanteric procedure may be required to restore abductor mechanics and avoid secondary impingement (34, 35). Relative contraindications include advanced osteoarthritis, poor bone quality, marked obesity, and neuromuscular disorders (1, 34).

Technique

Intertrochanteric osteotomy for coronal plane correction is usually fixed with a fixed-angle proximal femoral locking plate, commonly a pediatric hip plate, which accepts both conventional and locking screws with proximal screw angles between 105 and 120° (34). This allows concomitant surgical hip dislocation and avoids the cumbersome and technically demanding maneuver of threading the greater trochanter using a blade plate. Preoperative planning measures the current neck–shaft angle and defines the required correction angle α. The plate angle γ determines the guide-wire angle β: for varization, β = γ + α, and for valgization, β = γ − α.

The approach extends the surgical hip dislocation distally in the subvastus plane. Two 2.5 mm Kirschner wires are inserted proximal and distal to the osteotomy as rotation markers. After provisional fixation of the trochanter, the locking plate is positioned laterally below the greater trochanter and guide wires are inserted through the plate at angle β under fluoroscopy. The plate is removed, the osteotomy is made, and the plate is advanced again over the guide wires. For variation, the cut ascends from lateral-distal to medial-proximal using the calcar area as a hinge. Proximal screws are inserted, and the distal shaft is then reduced with torsional correction if required before final compression fixation. Flexion correction is achieved by anterior rotation of the plate around the transverse axis, and extension correction by posterior rotation. Wedge removal is usually avoided to preserve limb length; open gaps can be filled with cancellous bone from the trochanteric osteotomy (11).

Postoperatively, 10–20 kg partial weight bearing is maintained for 6–8 weeks, and active abductor strengthening is delayed until radiographic healing of the trochanteric osteotomy is evident (Fig. 5).

Trochanteric osteotomy (relative neck lengthening)

Indication

Relative trochanteric overgrowth develops when proximal femoral growth disturbance spares the greater trochanter, allowing it to overgrow relative to the femoral head and neck (37). It is typical after ischemic injury to the capital femoral epiphysis or proximal growth plate, especially in Legg–Calvé–Perthes disease, after the treatment of developmental dysplasia, in slipped capital femoral epiphysis sequelae, and after infection. Biomechanically, the elevated trochanter shortens the abductor lever arm and reduces gluteus medius and minimus efficiency (38). At the same time, it causes extra-articular impingement between the trochanter and pelvis during abduction and extension. This often coexists with coxa brevis and varus neck morphology causing additional intra-articular impingement (39, 40). The typical findings are Trendelenburg gait and pain with abduction in extension related to a broad ischiofemoral impingement. Trochanteric distalization is indicated when symptoms persist despite targeted abductor rehabilitation.

Technique

Using the same approach as for surgical hip dislocation, with the trochanteric fragment already mobilized and the joint assessed intra-articularly, the transfer is performed after sufficient base resection has created clearance. The trochanteric osteotomy is performed as a flat gliding cut from the tip of the greater trochanter to the innominate tubercle, creating a fragment 1–1.5 cm thick carrying gluteus medius and vastus lateralis. After standard surgical hip dislocation and intra-articular assessment, the essential step is controlled resection of the stable trochanteric base down to the base of the femoral neck to create pelvitrochanteric clearance (40). This is done with the hip reduced and internally rotated, using a piecemeal osteotome technique. The trochanter is then distalized according to the preoperative plan, usually with slight anteriorization, until the tip lies approximately at the level of the hip rotation center. Position is checked fluoroscopically and by dynamic testing. If dorsal tilting occurs because of gluteus minimus tension, selective tendon release can be required (41). Definitive fixation is obtained with two or three 3.5 mm screws, and the gap is filled with autologous cancellous bone.

Femoral neck osteotomy (true femoral neck osteotomy)

Indication

Femoral neck osteotomy allows intra-articular correction at the level of the femoral neck through surgical hip dislocation and the extended retinacular flap (12). Because the osteotomy is close to the center of deformity, larger corrections are possible with less secondary deformity and less limb shortening than with more distal osteotomies. The procedure is best suited to adolescents and young adults. Main indications include severe isolated valgus deformity with ischiofemoral impingement, where neck-level varus correction increases offset without the secondary shaft displacement of a more distal osteotomy; post-traumatic deformity near the head–neck junction; residual slipped capital femoral epiphysis after physeal closure. Focal osteonecrosis is a relative indication when a viable weight-bearing segment can be rotated into the load zone. Femoral neck osteotomy is not the procedure of choice for isolated torsional abnormality because torsion is not corrected at this level. Multiplanar corrections at the neck level to address additional torsional deformities are possible but technically demanding. Contraindications include an open physis, extensive osteonecrosis without sufficient viable bone, and advanced osteoarthritis (12).

Technique

Through surgical hip dislocation with an extended retinacular flap, the basal femoral neck is exposed circumferentially, while the vascular sleeve is mobilized and protected. For an open-wedge varus osteotomy, a guide wire is inserted under fluoroscopy perpendicular to the shaft through the basal neck in the calcar region. The osteotomy follows this plane while preserving the medial cortex as a hinge. The osteotomy is gradually opened with a spreader to the desired correction, usually not more than 30–35°, and the gap is filled with autologous bone. Fixation is achieved with two or three parallel fully threaded 4.5 mm cortical screws. For closed-wedge varization, a medial wedge is removed to obtain a horizontal contact line and compression is achieved with lag screws. For valgus correction, a lateral wedge is removed and the redundant retinacular flap must be adapted carefully to avoid kinking. In post-physeal slipped capital femoral epiphysis, the shortened posterosuperior retinacular flap often requires more distal mobilization. In focal avascular necrosis, rotational osteotomy can move the necrotic segment out of the weight-bearing zone; posterior rotation is preferred because the flap is not submitted to tension. After fixation, femoral head perfusion is checked with drill-hole bleeding or laser Doppler flowmetry (30). In the reported 16-hip adult series, no avascular necrosis occurred (12). Postoperatively, 10–15 kg partial weight bearing is maintained for 10–12 weeks (Fig. 6).

Femoral head reduction osteotomy

Indication

Femoral head reduction osteotomy is a rare salvage procedure for symptomatic coxa magna, most commonly in Perthes sequelae. The enlarged aspherical head causes incongruity, hinged abduction, impingement, and progressive cartilage damage that cannot be corrected with extra-articular osteotomy alone. The procedure is performed through surgical hip dislocation with an extended retinacular flap to preserve perfusion during central head resection. It is indicated only when symptomatic asphericity is accompanied by demonstrable hinged abduction and sufficiently preserved peripheral cartilage, typically around a central saddle defect or necrotic core. The aim is to reduce and increase the sphericity the head, improve containment and range of motion, and postpone arthroplasty. At least half of the enlarged head should remain after resection, and a stable medial head–neck pillar must be preserved (42). A globally destroyed head or unreconstructable articular surface is a contraindication.

Technique

After surgical hip dislocation and preparation of the superior retinacular flap, the cartilage and labrum are inspected to confirm the indication. A patient-specific cutting guide can be positioned on the anterior head–neck junction. The lateral cut respects the course of the lateral retinaculum, while the medial cut preserves a bone bridge of at least 15 mm. Osteotomies are made through the guide slots with an oscillating saw under irrigation and are extended at least 1 cm caudally into the femoral neck toward the neck base. After removal of the guide, the cuts are completed posteriorly under direct vision. The lateral and intermediate segments are mobilized, the cut surfaces are checked for vital bleeding, and the main fragment is reduced manually until a congruent step-free surface is obtained. Fixation is performed with two 3.5 mm screws placed through the neck portion of the mobile fragment toward the contralateral stable neck cortex. Screw prominence must be avoided. After reduction, containment, and stability are reassessed, a concomitant periacetabular osteotomy should be considered if these are insufficient. Computer-assisted three-dimensional planning and patient-specific cutting guides improve precision in this technically demanding procedure (43) (Fig. 7).

Outcomes

The outcome literature on proximal femoral osteotomy is heterogeneous because indications, deformities, and techniques differ substantially. Historical intertrochanteric osteotomy series reported ten-year survival rates between 50 and 89% (4). More contemporary series benefit from direct cartilage assessment, more accurate deformity analysis, and treatment of concomitant intra-articular pathology at the index procedure.

For rotational osteotomy, Mastel et al. reported improved patient-reported outcomes after femoral derotation osteotomy in adults with decreased femoral anteversion, although early nonunion and later hardware removal were the main reasons for reoperation (44). A recent systematic review of 97 femoral rotational osteotomies across seven studies also found a consistent postoperative improvement, but the reported unplanned reoperation rate was about 40%, mostly because of hardware removal rather than failure of the corrective concept itself (45). Moreover, a comparative series in patients with femoral retroversion found that femoral rotational osteotomy, alone or combined with hip arthroscopy, resulted in a greater functional improvement and higher rates of clinically meaningful outcome achievement than isolated arthroscopy alone (46).

For relative femoral neck lengthening, Albers et al. reported reduced pain, improved abductor strength, and improved range of motion in hips with a high-riding trochanter, although osteoarthritis progression was not prevented in all cases (39). In a newer retrospective series with 60 symptomatic residual deformities after Legg–Calvé–Perthes disease treated with surgical hip dislocation, femoral head reshaping, and relative femoral neck lengthening, mid-term outcomes showed an improvement in deformity and symptoms (47).

For femoral neck osteotomy, Rego et al. reported healing in all cases and no postoperative avascular necrosis in 16 adult hips, along with a substantial improvement in functional scores (12).

For femoral head reduction osteotomy, early computer-assisted experience showed improved sphericity and technical feasibility (43). More recent clinical series reported improved morphology and patient-reported outcomes at short- to mid-term follow-up, with no symptomatic avascular necrosis in the 2025 series, but the cohorts remain small and combined acetabular reorientation is frequently required (48, 49).

Conclusion

Proximal femoral osteotomy is a deformity-specific, joint-preserving procedure for selected patients with symptomatic proximal femoral deformity and preserved cartilage. It is not a substitute for arthroplasty once joint destruction is established.Surgical hip dislocation, and when necessary, the extended retinacular flap, allows correction close to the deformity while preserving femoral head perfusion and treating associated intra-articular pathology.Extra-articular osteotomies remain appropriate for isolated torsional or multiplanar deformities; femoral neck and femoral head osteotomies should be reserved for selected indications in experienced hip preservation centers.Preoperative cartilage status, patient age, timing of correction, and technical precision are the main determinants of outcome.

ICMJE Statement of Interest

The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the work reported.

Funding Statement

This work did not receive any specific grant from any funding agency in the public, commercial, or not-for-profit sector.