Written by manual therapist Roar Syltebø

Passive internal rotation of the hip joint is used in the classification and diagnosis of both hip complaints and low back pain (Altman et al., 1991; Flynn et al., 2002; Juel, 2007; Ombregt et al., 2002). Clinicians who examine patients with hip, pelvic and low back pain should therefore be able to perform and interpret passive movement tests of the hip.

Indication

Passive internal rotation of the hip is indicated in pain or other symptoms that may originate from the hip, pelvis or low back. The test should be used routinely in all examinations of these regions.

Procedure

Passive internal rotation of the hip joint can be examined in prone (Flynn et al., 2002; Magee, 2007; Ombregt et al., 2002; Solberg & Kirkesola, 2007), supine (Cook & Hegedus, 2012; Magee, 2007; Ombregt et al., 2002) and sitting (Norkin & White, 2003; Reese & Bandy, 2002).

In prone, the knee is flexed to 90°. The examiner moves the lower leg and foot outwards with one hand, while the other hand stabilises the pelvis/sacrum. At end range, gentle overpressure is applied to assess the end-feel (Magee, 2007; Solberg & Kirkesola, 2007).

Both hips can also be tested simultaneously by moving both lower legs outwards. The pelvis then does not need to be stabilised, as the feet act as counterforce for each other. When both sides are tested at the same time, it is often easier to assess differences in range between the right and left sides (Ombregt et al., 2002).

In supine, the hip is flexed to 90° and the thigh is held vertical while the lower leg is moved outwards. This produces internal rotation of the hip joint. One of the examiner’s hands stabilises the patient’s knee, while the other applies gentle overpressure to assess the end-feel (Cook & Hegedus, 2012; Ombregt et al., 2002).

The sitting position is used in several sources when range of motion is measured with a goniometer (Birrell et al., 2001; Norkin & White, 2003; Reese & Bandy, 2002). Goniometric measurement is not yet described in Body Examination. Nussbaumer and colleagues (2010) found that the goniometer gave higher values than an electromagnetic tracking system, because it measures the angle between body segments rather than true hip joint motion alone. Agreement with the tracking system was nevertheless good for internal rotation (ICC 0.88), and test–retest reliability was good (ICC above 0.90). Measurements taken by the same examiner are therefore well suited to monitoring change over time (Nussbaumer et al., 2010).

Agreement between different examiners is poorer. In patients with hip osteoarthritis, Poulsen and colleagues (2012) found only poor to moderate inter-examiner reliability for internal rotation measured in supine (ICC 0.44–0.63), with a standard error of measurement (SEM) of 9–10°. The authors estimate that a difference of at least approximately 20° is needed before it can be distinguished from measurement error when two different examiners measure. Comparison with the opposite side by the same examiner is therefore more reliable than comparing values in degrees between examiners (Poulsen et al., 2012).

It is worth noting that the sitting position gives the same hip position as supine with 90° of flexion, whereas the prone position tests the joint without flexion, in neutral. Klässbo and colleagues found that some patients with a marked extension deficit could not be tested in neutral (Klässbo et al., 2003).

Body Examination recommends that passive flexion, passive internal and external rotation, the P4 test, the POSH test, the scour test and the FADIR test be assessed together as a graded examination sequence for the hip joint, with loading increased stepwise through progressive compression, adduction, rotation and range of motion. Clinical experience suggests that sensitivity increases and specificity decreases as provocation is intensified. The early steps are therefore most informative when positive, and the later steps most informative when negative. This has not been studied for the sequence as a whole, but it is consistent with the most provocative hip tests in the literature showing consistently high sensitivity and low specificity. Pain location, the step at which pain is provoked, and any restriction in range of motion should be interpreted together.

Interpretation

The test is interpreted as positive when range of motion is reduced compared with the opposite side and/or the test reproduces the patient’s familiar pain, particularly towards end range.

Normal range of motion varies between individuals. In a Norwegian study of 761 healthy individuals from four years of age to adulthood, most hip movements decreased with age, and women had greater internal rotation than men (Svenningsen et al., 1989). Absolute cut-off values should therefore be interpreted with the patient’s age and sex in mind, and comparison with the opposite side is often more informative than the number of degrees alone.

In the Cyriax tradition, the capsular pattern of the hip joint is markedly reduced internal rotation, abduction and flexion, less reduced extension, and little or no reduction of adduction and external rotation (Klässbo et al., 2003; Ombregt et al., 2002). Several articles have questioned the significance of the capsular pattern (Bijl et al., 1998; Greenwood et al., 1998), but most of the sources we have found agree that arthritis, an intra-articular lesion or osteoarthritis of the hip joint reduces passive internal rotation (Altman et al., 1991; Bijl et al., 1998; Birrell et al., 2001; Chan et al., 2005; Cook & Hegedus, 2012; Dorrell & Catterall, 1986; Klässbo et al., 2003; Koc et al., 2025; Magee, 2007; Ombregt et al., 2002; Solberg & Kirkesola, 2007; Steultjens et al., 2000). Pain towards end range points in the same direction.

There are three conditions in particular in which passive internal rotation of the hip has been found to be a useful examination. The first and most important is hip osteoarthritis (Agricola et al., 2013; Altman et al., 1991; Holla et al., 2012; Koc et al., 2025; Metcalfe et al., 2019; Ombregt et al., 2002; Steultjens et al., 2000; Sutlive et al., 2008). The second is intra-articular hip pathology such as labral tears and femoroacetabular impingement (FAI) (Albertoni et al., 2023; Chan et al., 2005; Fitzgerald, 1995; Griffin et al., 2016; Pålsson et al., 2020; Reiman et al., 2013; Santori & Villar, 2000). The third is distinguishing hip pain from low back pain (Brown et al., 2004; Greenwood et al., 1998).

Hip osteoarthritis

Cyriax systematised the functional examination of the musculoskeletal system with active, passive and resisted tests (Kaltenborn, 2011; Klässbo et al., 2003; Ombregt et al., 2002). Passive tests are regarded as particularly important in the diagnosis of intra-articular lesions (ibid.). Several studies confirm that reduced and painful passive hip movements are associated with hip osteoarthritis. Cyriax’s capsular pattern (reduced internal rotation, abduction and flexion), however, has not been reproduced, but rather refuted, in scientific studies (Bijl et al., 1998; Klässbo et al., 2003).

In 2001, Birrell and colleagues found that internal rotation was the most restricted movement in hip osteoarthritis. Flexion and external rotation were also reduced, but considerably less so. If movement was restricted in one of the three directions (internal rotation, external rotation or flexion), they found a sensitivity of 86% for moderate and 100% for severe osteoarthritis, with a specificity of 54% and 42%, respectively. If movement was restricted in all three directions, sensitivity fell to 33% for moderate and 54% for severe osteoarthritis, while specificity rose to 93% and 88%. Rotation was examined in sitting (Birrell et al., 2001).

In 2003, Klässbo and colleagues found that internal rotation was the movement most often restricted in hip osteoarthritis. Nevertheless, 13 of 77 patients with unilateral hip osteoarthritis had greater internal rotation on the affected side (Klässbo et al., 2003).

The American College of Rheumatology (ACR) has included internal rotation of the hip as a key clinical criterion in its criteria for the classification of hip osteoarthritis (Altman et al., 1991). The criteria describe two clinical combinations: painful internal rotation of 15° or more, morning stiffness of the hip of 60 minutes or less and age 50 years or older; or internal rotation of less than 15° together with hip flexion of 115° or less. The clinical criteria had a sensitivity of 86% and a specificity of 75% (Altman et al., 1991). In other words, when internal rotation is clearly reduced, reduced flexion is sufficient in addition, whereas less pronounced loss of internal rotation requires additional criteria such as pain on internal rotation, morning stiffness and age.

Holla and colleagues (2012) examined 598 patients with early symptomatic hip and/or knee osteoarthritis in the Dutch CHECK cohort. Range of motion was measured actively with a goniometer. In patients with hip symptoms, internal rotation of less than 24° best distinguished those with and without radiographic features of osteoarthritis (osteophytes or joint space narrowing). The ACR criterion of internal rotation of less than 15° increased the probability of radiographic features from 25% to 58%, but identified few of the patients. The authors therefore recommend a cut-off of 24° in early symptomatic hip osteoarthritis (Holla et al., 2012).

Sutlive and colleagues (2008) developed a clinical prediction rule for hip osteoarthritis in patients over 40 years of age with unilateral hip pain, using radiographs as the reference standard. The rule consists of five variables: passive internal rotation of 25° or less, a positive scour test, hip pain on squatting, lateral hip pain on active hip flexion and pain on active hip extension. Internal rotation was measured in prone, with the hip in neutral and the knee flexed to 90°. Three of five positive findings gave a positive likelihood ratio of 5.2, and four of five a positive likelihood ratio of 24.3, although with a very wide confidence interval (4.4–142.1). The rule has not been validated in new patient populations and should be used with caution (Sutlive et al., 2008).

The American Physical Therapy Association (APTA) clinical practice guideline for hip osteoarthritis recommends, with a grade A recommendation (strong evidence), that adults over the age of 50 be classified as having hip osteoarthritis with hip pain and mobility deficits on the basis of the following findings: moderate anterior or lateral hip pain during weight-bearing activities, morning stiffness lasting less than one hour after waking, hip internal rotation range of motion of less than 24° or internal rotation and hip flexion 15° less than the non-painful side, and/or increased hip pain associated with passive hip internal rotation. The recommendation is carried over from the 2017 version, and the authors found no substantial new research on diagnosis in the update. The 24° cut-off is consistent with the findings of Holla and colleagues (2012). The APTA clinical practice guideline for hip osteoarthritis also states that internal rotation and flexion are typically the first movements to be restricted, while all hip movements may become reduced and painful as the degeneration progresses. It notes that range of motion varies between individuals because of differences in femoral version and acetabular alignment, and recommends (grade A) that passive range of motion in all directions, including internal and external rotation, be documented in all patients with hip pain or hip osteoarthritis (Koc et al., 2025).

A 2019 systematic review in the JAMA series “The Rational Clinical Examination” pooled studies using radiographs as the reference standard. Reduced internal rotation of the hip (four studies, 788 hips) had a sensitivity of 66% and a specificity of 79%, with a positive likelihood ratio of 3.2 (95% CI 1.7–6.0) and a negative likelihood ratio of 0.43 (0.31–0.60). Pain on internal rotation was more sensitive (82–88%) but had low specificity (38–39%), with a positive likelihood ratio of 1.4 and a negative likelihood ratio of 0.31–0.45. The authors conclude that simple tests of hip motion, and pain elicited during them, can help identify patients with radiographic hip osteoarthritis, but that no single test is sufficient on its own (Metcalfe et al., 2019).

In 2007, Tarasevicius and colleagues found that hip osteoarthritis is largely associated with reduced elasticity of the joint capsule of the affected hip (Tarasevicius et al., 2007). Indirectly, this can be interpreted to mean that range of motion decreases and the end-feel becomes firmer in advanced hip osteoarthritis (ibid.).

Reduced internal rotation may also be of prognostic significance. Agricola and colleagues (2013) followed 1,002 patients with early symptomatic osteoarthritis in the Dutch CHECK cohort for five years, using internal rotation of 20° or less as a clinical sign of cam impingement. Severe cam morphology (alpha angle above 83°) substantially increased the risk that the hip developed end-stage radiographic osteoarthritis (Kellgren–Lawrence grade 3–4) or underwent total hip replacement (adjusted odds ratio 9.7). Combined with reduced internal rotation, the association was even stronger, and 52.6% of these hips reached one of these end points during follow-up (Agricola et al., 2013).

Labral tears and femoroacetabular impingement

In 1986, Dorrell and Catterall presented eleven patients with labral tears. Four of them experienced sharp groin pain or a click in the hip on passive internal rotation in 90° of flexion (Dorrell & Catterall, 1986).

In 1999, Hase and Ueo published an article on the arthroscopic diagnosis of labral tears. Seven of ten patients had pain on passive internal rotation of the hip in 90° of flexion, i.e. a sensitivity of 70% (Hase & Ueo, 1999).

In 2000, Santori and Villar published a study of 76 patients with confirmed acetabular labral tears. The authors do not report how many patients had painful passive internal rotation, but emphasise that painful, but not restricted, internal rotation was regarded as an important clinical sign of a labral tear (Santori & Villar, 2000).

Chan and colleagues (2005) investigated the value of MR arthrography in diagnosing labral tears of the hip in 30 patients. Pain, but not restricted range of motion, on internal rotation in 90° of hip flexion was regarded as very useful in the clinical examination. Here too, no figures are given for how many patients had a positive finding, so sensitivity and specificity cannot be calculated (Chan et al., 2005).

Cook and Hegedus (2012) report a sensitivity of 100% for passive internal rotation in the studies by Hase and Ueo (1999), Santori and Villar (2000) and Chan and colleagues (2005). We have not been able to find this in any of these articles. On the contrary, Hase and Ueo found a sensitivity of 70% (Chan et al., 2005; Cook & Hegedus, 2012; Hase & Ueo, 1999; Santori & Villar, 2000).

A systematic review with meta-analysis found a pooled sensitivity of 96% and a specificity of 17% for pain on passive internal rotation in 90° of hip flexion (the flexion–internal rotation test), with a positive likelihood ratio of 1.12 and a negative likelihood ratio of 0.27. The analysis was based on only three studies with a total of 42 patients. The test is thus sensitive but has very low specificity, and is better suited to ruling out than to confirming intra-articular hip pathology (Reiman et al., 2013).

Pålsson and colleagues (2020) examined 63 patients (69 hips) with longstanding groin and hip pain and suspected FAI syndrome. Reduced passive internal rotation in neutral had a specificity of 94%, whereas reduced internal rotation in 90° of hip flexion had a specificity of 63%. Sensitivity of the range of motion tests was low (29–56%). Inter-examiner reliability for internal rotation was moderate (kappa above 0.4). The authors conclude that reduced internal rotation in neutral is useful for confirming FAI syndrome, whereas sensitive provocation tests such as the FADIR test are more useful for ruling it out, and that the combination can increase diagnostic accuracy (Pålsson et al., 2020).

A 2023 systematic review with meta-analysis (17 studies, 1,702 hips) found that patients with FAI syndrome had reduced internal rotation compared with healthy controls, on average approximately 8° in 90° of hip flexion and 6° in neutral, with moderate certainty of evidence. In people with asymptomatic FAI morphology (cam or pincer), the authors found no definite restriction, although the evidence here was very uncertain. The authors therefore suggest that symptoms, and not only joint shape, contribute to the restriction of movement, and that passive range of motion of the hip should be a central part of the clinical examination (Albertoni et al., 2023). The differences are small in degrees, which underlines the importance of comparing with the opposite side.

The international consensus on FAI syndrome (the Warwick Agreement) defines the condition as a combination of symptoms, clinical signs and imaging findings. The consensus states that hip range of motion is often restricted, typically internal rotation in flexion, and that impingement tests must reproduce the patient’s familiar pain to be considered positive (Griffin et al., 2016). The later Zurich consensus from the International Hip-related Pain Research Network concludes that both clinical examination and imaging have limited diagnostic utility on their own, and that the diagnosis should be based on an overall assessment. A negative FADIR test can help rule out hip-related pain (Reiman et al., 2020).

Hip or low back?

In 2004, Brown and colleagues evaluated examination findings that can distinguish pain originating from the low back from pain originating from the hip joint. They found that reduced internal rotation of the affected hip made it considerably more likely that the pain originated from the hip joint rather than the low back (Brown et al., 2004).

A 2019 systematic review found that reduced internal rotation was the only restriction of hip movement significantly associated with non-specific low back pain. The quality of the evidence was very low, and the authors emphasise that the finding should be interpreted with caution (Avman et al., 2019). Slightly reduced internal rotation may therefore also occur in patients with low back pain and must be interpreted together with the other findings.

Hip internal rotation of more than 35° is also part of a clinical prediction rule for classifying patients with low back pain (Flynn et al., 2002). The prediction rule is described in Body Examination’s category for clinical decision rules.

Body Examination suggests the following interpretation of passive internal rotation of the hip

• Reduced internal rotation, with or without pain, points towards hip osteoarthritis. Internal rotation of less than 24° or clearly less than on the opposite side, concomitant reduced flexion, pain on passive internal rotation, morning stiffness and age over 50 strengthen the suspicion, but no single test is sufficient on its own.
• Sharp groin pain without restricted range of motion on passive internal rotation in 90° of hip flexion points towards intra-articular involvement such as a labral tear or FAI. The finding is sensitive but has low specificity, and the test should be supplemented with the FADIR test and the other tests in the graded hip examination sequence.
• Reduced internal rotation in neutral compared with the opposite side strengthens the suspicion of intra-articular hip involvement.
• Clearly reduced internal rotation of the hip joint points towards the hip joint rather than the low back as the cause of the patient’s pain, but slightly reduced internal rotation also occurs in low back pain.
• Range of motion varies with age and sex, and measurement error between different examiners is large. Comparison with the opposite side by the same examiner is therefore more important than absolute values in degrees.
• The test has been little studied as a single test, but passive internal rotation of the hip is very widely used in clinical practice and should be mastered by everyone who examines patients with hip, pelvic and low back complaints.

Literature search, updating and translation were carried out with the assistance of AI (Claude, Anthropic). The professional content has been reviewed and quality-assured by the editor-in-chief, Roar Syltebø.

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