Invited Review

Hip-Spine Syndrome: Diagnostic and Rehabilitation Considerations for Clinicians

Preston Le, MD

University of Colorado School of Medicine

Aurora, CO

David M. Gallacher, MD, MBA

University of Colorado School of Medicine

Aurora, CO

Dustin Anderson, MD

The Steadman Clinic and Steadman Philippon Research Institute

Aspen, CO

Introduction

The evaluation and treatment of back or hip pain is challenging due to the multifactorial interplay between several etiologies that culminate in the symptoms experienced by affected patients. Hip-Spine Syndrome (HSS) encompasses this interplay and is characterized by overlapping pathologies of the hip joint and lumbar spine that result in complex, interrelated pain presentations and compensatory biomechanics.1

HSS was first described by Offierski and MacNab (1983) as a “mechanical interaction between the hip and spine” and interest in this topic has grown substantially, particularly over the past 5 years.2 HSS affects a wide age group, ranging from athletic to aging populations, and misdiagnosis can lead to suboptimal outcomes after hip arthroscopy or lumbar interventions that only address one component of the syndrome.3

A comprehensive review of HSS was previously published in SpineLine in 2021, highlighting the diagnostic pitfalls, broad differential diagnosis, and importance of a structured clinical evaluation to avoid misdiagnosis and unnecessary intervention. That work remains highly relevant for spine providers, particularly given the frequency with which patients with overlapping hip and lumbar pathology present to spine-focused practices.

Since that publication, however, there has been rapid growth in the literature clarifying spinopelvic biomechanics, radiographic parameters, diagnostic injection utility, and surgical sequencing considerations across hip and spine disciplines. A recent bibliometric analysis identified total hip arthroplasty, spinopelvic biomechanics, and disease classification as the dominant emerging research themes, while also highlighting the absence of universally accepted diagnostic and treatment standards.4 The present review is intended as a concise update that synthesizes these more recent advances, with particular emphasis on spinopelvic alignment, functional biomechanics, and interdisciplinary management strategies that are directly applicable to spine providers.

Pathophysiology and Biomechanics of the Hip-Spine Relationship

Functional mobility requires an interdependent relationship between hip and spine biomechanics. Dysfunction can start from either location, as the hip and spine operate as a functional unit linked through the pelvis.5 During hip flexion, the pelvis posteriorly tilts and lumbar lordosis decreases; during hip extension, anterior pelvic tilt increases lumbar lordosis.6 Loss of motion in either region, alters compensatory mechanics in the other.

Hip-driven compensation from limited hip motion (eg, femoroacetabular impingement, labral tear) that reduces hip flexion and internal rotation can increase compensatory lumbar motion in the form of lumbar extension and facet loading which can cause pain or spondylosis.

Conversely, fixed sagittal imbalance or lumbar stiffness that results in spine-driven compensation restricts pelvic motion via hip hyperflexion, altering hip loading and contributing to impingement.7

Classification of Hip-Spine Syndrome

HSS can be classified as primary hip syndrome, primary spine syndrome, or complex (secondary) HSS. Each reflects the dominant source of pathology. Primary hip syndrome involves hip pathology driving compensatory spinal changes, whereas primary spine syndrome involves lumbar pathology altering pelvic tilt and hip mechanics. Complex HSS involves concurrent pathology in both regions, and a single diagnosis is often insufficient.1,8

Diagnostic Approach

Key developments since the SpineLine HSS review in 2021 include improved characterization of spinopelvic stiffness and mobility phenotypes, growing evidence linking sagittal imbalance to postoperative instability, expanded use of standing and seated spinopelvic imaging, and emerging data on optimal surgical sequencing in patients with combined hip and spine pathology. However, diagnosis of HSS, as with all complex disorders, begins with obtaining a thorough history of symptoms, pain localization, and functional history.

History

Pain localizing to the low back, particularly when worsened by extension- or flexion-based activities, more often suggests a spinal etiology. Axial sources (eg, facetogenic, vertebrogenic) typically present as midline, activity-dependent pain with positional features and without neurologic deficits.9,10

Radicular features—such as pain radiating below the knee with numbness or tingling—further support a spinal source; however, these presentations are variable, as symptoms may extend beyond classic dermatomal distributions. Additionally, dull, poorly localized lower extremity pain is common in nonradicular spinal etiologies, and facetogenic or vertebrogenic pain may produce proximal or distal radiation without nerve root involvement.11

In contrast, pain localizing to the groin is more suggestive of intra-articular hip pathology and is often accompanied by functional limitations, such as difficulty tying shoes or exiting a vehicle, although referral to the lateral or posterior thigh and buttock may also occur.12

While these historical features can help generate an initial suspicion of pain etiology, they frequently overlap and may be misleading; therefore, history should be considered hypothesis-generating rather than diagnostic and integrated with physical examination, imaging, and, when appropriate, diagnostic procedures.

Physical Examination

Physical examination for HSS should include provocative maneuvers for the spine and hip including the Flexion, Adduction, Internal Rotation (FADIR), Flexion, Abduction, External Rotation (FABER), straight leg raise, slump test, as well as range of motion (ROM) testing of both the spine and hips. A positive FADIR test reproduces anterior/groin pain due to hip impingement. Pain in the groin with FABER, as discussed in history gathering, indicates hip pathology. Pain in buttocks with FABER is likely more due to SI joint/spine pathology. Examining gait is also critical as an antalgic gait with shortened stance phase or Trendelenburg can be more indicative of hip-driving pathology versus gait characterized by neurogenic claudication being more indicative of spinal pathology.9,13

Imaging

Standard imaging includes plain radiographs and MRI to assess hip (labral/cartilage integrity or CAM/pincer morphology) and spinal pathology (disc disease, foraminal stenosis). Standing/seated lateral spinopelvic films to assess mobility and sagittal balance are especially helpful.

Hip and spine pathology commonly coexist on MRI, even when one is asymptomatic. Pan et al. demonstrated a correlation between hip joint disease and asymptomatic lumbar MRI abnormalities, particularly with L4–L5 facet degeneration.14 Harris (2022) described the pelvis as the “lowest vertebral level,” emphasizing that the hip cannot be evaluated in isolation from the spine.13

Functional spinopelvic assessment using comparative standing and seated radiographs—particularly the evaluation of pelvic tilt and lumbar motion during sit-to-stand transitions—may help predict postoperative dislocation risk following total hip arthroplasty. This form of “dynamic” evaluation refers to radiographic assessment of positional change rather than motion capture or laboratory-based analysis and can be performed as part of routine physician-directed imaging.6

There are radiographic spinopelvic parameters that can predict instability and ultimately pain. Pelvic incidence (PI), sacral slope (SS), and pelvic tilt (PT) define sagittal balance. High PI or abnormal spinopelvic mobility predicts postoperative instability and can help physicians recognize whether a patient is a hip-user (ie, relying on hip motion) or spine-user (ie, relying on lumbar motion), which guides both rehabilitation and surgical decision-making.5

Spinopelvic alignment parameters, including pelvic incidence–lumbar lordosis (PI–LL) mismatch, are typically measured on upright sagittal radiographs, often using biplanar or EOS imaging, with a mismatch greater than 10° commonly considered indicative of sagittal imbalance. Advanced modalities, such as three-dimensional gait analysis and dynamic MRI provide complementary functional information regarding pelvic motion and spine–hip coordination.

Diagnostic (and Possibly Therapeutic) Injections

Image-guided injections (such as intra-articular hip injections) under ultrasound or fluoroscopy are valuable diagnostic adjuncts in patients with suspected hip–spine syndrome, and have demonstrated high diagnostic accuracy (sensitivity and specificity >90%) in differentiating hip from spinal pain generators. Temporary symptom relief following an intra-articular hip injection with local anesthetic, with or without corticosteroid, supports a primary hip source, whereas persistent pain suggests a spinal etiology. Conversely, selective nerve root or facet joint injections may help localize a spinal pain generator when hip pathology is less likely.10,16

Treatment

Nonoperative Management

HSS treatment begins with a multimodal regimen of pain medications such as NSAIDs, topical therapy, manual therapy, and physical therapy, all of which aim to promote optimal movement patterns.

Education on the diagnosis and management of hip-spine syndrome can support therapists in implementing targeted interventions. Physical therapy should focus on improving core and hip strength, postural training, and range of motion. Generally, prescriptions would focus on strengthening and mobilizing both the hip and spine, as a dual-region rehabilitation approach may be more effective than region-isolated programs that address only one of these areas.

Guidance can also be offered for modifying activity to avoid excessive lumbar hyperextension or repetitive hip impingement positions.

Operative Management

If both hip and spine pathology require surgery, it is unclear whether addressing the hip or spine first is optimal.17,18 The consensus is to identify the dominant driver of pain (hip versus spinal source), then address it, as this results in improved outcomes, as discussed in Edwards et al, who demonstrated that a “one-size-fits-all” approach fails.19 Intervention should be tailored based on functional and radiographic spinopelvic profiles, as spinopelvic stiffness predicts poorer outcomes after hip arthroscopy and may necessitate concurrent or staged spine correction.

Postoperative management and rehabilitation should focus on maintaining mobility, proper postural alignment, stability, gait training, and minimizing harmful compensations to prevent the recurrence of HSS.1,3,8

Future Directions

Ultimately, improved diagnostic criteria, functional imaging protocols, and treatment pathways are paramount to optimal management of HSS. In imaging, new advances in artificial intelligence may aid in analyzing plain radiographs, dynamic MRI, and 3D gait analysis to quantify spinopelvic balance and thereby reduce the risk of instability and pain. Additionally, the known quantity of HSS in younger, athletic, and nonarthritic populations is likely an underestimation of the true disease burden, given biases of epidemiological schema.

Conclusion

In summary, HSS is a continuum of disease that can originate from either the hip or spine rather than a binary diagnosis. Effective management of HSS relies on a systematic approach that combines a comprehensive history and physical examination with targeted imaging informed by spinopelvic alignment parameters and the judicious use of diagnostic injections. Treatment should address the dominant pain generator, though providers should also recognize that Occam’s razor should not be the only approach given the complex interplay of pathology in HSS.19

While the foundational principles outlined in prior comprehensive reviews remain valid, recent advances in spinopelvic biomechanics, imaging, and treatment sequencing justify renewed attention to hip-spine syndrome. This updated review aims to provide spine providers with a focused, clinically actionable framework that reflects current evidence and evolving interdisciplinary practice. Future directions in HSS should be driven by more randomized controlled trials, dynamic functional assessments, AI-assisted interpretation of imaging, and individualized rehabilitation.