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Pronator, Lacertus and Anterior Interosseous Nerve Syndromes

High median nerve compression: pronator syndrome (sensory, thenar/palm sparing distinguishes from CTS) and AIN palsy (pure motor, OK-sign), with observation-first management and decompression for refractory cases.

33 citationsUpdated Aug 2026

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Overview

Pronator syndrome is a clinical diagnosis of median nerve compression in the forearm, supported by subjective operative findings and postoperative relief rather than objective pathophysiology [4]. A reliable diagnosis requires a thorough understanding of median nerve anatomy, possible compression sites, and characteristic clinical findings [2]. The term pronator syndrome should be replaced with superficialis-pronator syndrome [9], while lacertus syndrome and superficialis-pronator syndrome must be clearly presented as distinct targets for surgical release [9]. Concurrent carpal tunnel syndrome is rarely considered, and proximal compression sites are easily overlooked [8]. Electrodiagnostic testing, ultrasound, and MRI are not helpful in diagnosing pronator syndrome concurrent with carpal tunnel syndrome when clinical evaluation is the reference standard [15]. Furthermore, there is a paucity of controlled trials demonstrating that operative treatment for pronator syndrome is more effective than other treatments or sham surgery [4].

Surgical indications vary by specific nerve involvement. For pronator syndrome, surgical decompression is indicated for persistent symptoms lasting >6 months [1]. In contrast, anterior interosseous nerve syndrome requires a minimum of 12 months with no signs of motor improvement before surgery is indicated [1]. An isolated anterior interosseous nerve injury may not by itself be an indication for urgent surgery [19]. Surgical decompression of the median nerve or anterior interosseous nerve in the forearm is rarely indicated, and a prolonged nonsurgical approach is warranted in most cases [13].

Minimally invasive techniques offer effective decompression. Pronator teres symptoms disappeared in 93% of cases following a mini-invasive decompression technique [3]. The endoscopically assisted, minimally invasive approach adequately and safely decompressed all anatomical points of compression and improved DASH scores [12]. The author is a proponent of the endoscopic technique for pronator syndrome due to minimal damage and foresees its wide indication in the future [11].

Anatomy & Pathophysiology

Neural Compression and Clinical Indications

Pronator syndrome and anterior interosseous nerve syndrome require surgical indications including persistent symptoms for >6 months in pronator syndrome or a minimum of 12 months with no signs of motor improvement in anterior interosseous nerve syndrome [1]. Clinicians must have a thorough understanding of median nerve anatomy, possible sites of compression, and characteristic clinical findings of pronator syndrome to provide a reliable diagnosis [2].

Anatomical Variants and Compressive Structures

The ulnar head of the pronator teres is fibrotic or fibromuscular in 71.5% of cases [6]. The morphology and location of the ulnar head of the pronator teres relative to the median nerve are important for surgical treatment of pronator syndrome [6]. A study inventoried and mapped 6 potentially compressive structures neighboring or crossing the median nerve at the elbow and proximal forearm [37]. These 6 potentially compressive structures show precise proximal-to-distal locations with variations of 0.5 to 1.5 cm [37]. A case of median nerve entrapment at the elbow by a non-osseous fibrous ligament (Struthers) is presented [39].

Anterior Interosseous Nerve Pathology

Fascicular constrictions typify anterior interosseous nerve syndrome, identified in all MRN cases and 88% of ultrasound cases [7]. These fascicular constrictions are predominantly located in the posterior/posteromedial region proximal to the elbow joint line [7]. Details about the origin and course of the anterior interosseous nerve can explain the high percentage of anterior interosseous nerve palsy in supracondylar elbow fractures in children [40].

Traumatic and Rare Entrapments

Type 4 median nerve entrapment is a severe form of a rare complication of elbow dislocation [34]. The function of the pronator teres and quadratus cannot be isolated by elbow flexion positioning [29].

Classification

Pronator Syndrome: Pronator syndrome and anterior interosseous nerve syndrome are distinct clinical entities requiring specific diagnostic understanding of median nerve anatomy and compression sites [2]. The term "pronator syndrome" should be replaced with "superficialis-pronator syndrome" to distinguish it from lacertus syndrome [9].

Lacertus Syndrome: The term "lacertus syndrome" should refer to intermittent median nerve compression at the level of the lacertus fibrosus [18].

Bennett’s Syndrome: The pathology originally described by Bennett should be termed chronic exertional compartment syndrome of the pronator teres or "Bennett's syndrome" to resolve terminology confusion [18].

Anterior Interosseous Nerve Syndrome: Fascicular constrictions typify anterior interosseous nerve syndrome and were identified in all MRN cases and 88% of ultrasound cases [7].

Other Considerations: Concurrent carpal tunnel syndrome and pronator syndrome are rarely considered, and proximal compression sites are easily overlooked in these cases [8].

Clinical Presentation

Pronator syndrome is characterized by forearm pain ascribed to median nerve compression [27]. Clinical manifestations of proximal median nerve entrapment include aching pain in the anterior forearm [27]. Paraesthesias in the median nerve innervated region of the hand, similar to carpal tunnel syndrome, may also be present [27].

Motor deficits vary substantially in severity and completeness [27]. Clinical manifestations include loss of key and tip pinch strength [27]. Patients typically exhibit an inability to make an 'OK' sign [27]. Additional motor signs include loss of fine motor skills and a sense of clumsiness, including dropping objects [27].

Anterior interosseous nerve (AIN) palsy creates objective weakness and electrophysiological abnormalities [26]. In contrast, pronator syndrome lacks objective pathophysiology and is supported only by subjective operative findings and relief after surgery [4].

Diagnostic evaluation faces significant limitations. Nerve conduction studies are usually normal and unhelpful in the diagnosis of proximal median nerve entrapment [27]. Ultrasonography may not be easy to use for diagnosing proximal median nerve entrapment in the absence of a mass or haematoma, as fibrous bands or scar tissue may be too small to visualize [27]. Negative ultrasound findings cannot rule out the diagnosis of lacertus syndrome [24]. Localized tenderness over the lacertus fibrosus has limitations as a diagnostic indicator for lacertus syndrome [24]. Contralateral limb comparison is unreliable for diagnosing lacertus syndrome [24].

The diagnosis of pronator syndrome concurrent with carpal tunnel syndrome is challenging because electrodiagnostic, ultrasound, and MRI are not helpful when clinical evaluation is the reference standard [15]. The diagnostic process to differentiate pronator syndrome from carpal tunnel syndrome remains a challenge due to overlapping symptoms and limited reliable information in the literature [14]. It is essential for clinicians to have a thorough understanding of median nerve anatomy, possible sites of compression, and characteristic clinical findings of pronator syndrome to provide a reliable diagnosis [2]. It is important to take a complete history and perform a careful examination to avoid confirmation bias when evaluating throwers with medial elbow pain [5].

Investigations

Other Considerations: Diagnosis of pronator syndrome relies on a thorough understanding of median nerve anatomy, possible compression sites, and characteristic clinical findings to provide a reliable diagnosis [2]. Regarding anterior interosseous nerve syndrome, compression by normal surrounding tissues may not exist or is very rare, with most cases likely representing neuritis [30]. Conservative treatment for at least 6 months is recommended for anterior interosseous nerve syndrome before considering surgery [30].

Treatment

Non-Operative

Treatment for anterior interosseous nerve syndrome should begin nonsurgically with rest, splinting, and observation [17]. Most patients with anterior interosseous nerve syndrome improve without surgical intervention, supporting observation for several months before decompression [17]. There is a paucity of high-quality literature supporting the appropriate duration of conservative treatment for anterior interosseous nerve syndrome [17].

Operative

Indications: Surgical indications for nerve decompression in pronator syndrome include persistent symptoms for more than 6 months [1]. Surgical decompression is recommended for anterior interosseous nerve syndrome patients who have a space-occupying mass or who fail a several-month course of nonsurgical treatment [17].

Surgical Approach / Technique: The surgical approach for pronator syndrome or anterior interosseous nerve syndrome uses a lazy-S–type incision beginning proximal to the antecubital flexion crease to identify the median nerve proper and expose the ligament of Struthers if needed [17]. The surgical approach and extent of proximal exploration can be tailored to the surgeon's specific areas of preoperative concern [17]. During surgery, the median nerve is dissected free from the overlying lacertus fibrosus, the humeral head of the pronator teres, and the proximal fascial edge of the flexor digitorum superficialis arch [17]. Gantzer's accessory flexor pollicis longus muscle, if present, should be released during surgery for pronator syndrome or anterior interosseous nerve syndrome [17]. In patients with anterior interosseous nerve syndrome, the anterior interosseous nerve should be thoroughly decompressed from any overlying tissue and completely visualized as it travels into the distal forearm [17].

Outcomes: Pronator teres symptoms disappeared in 93% of cases following mini-invasive decompression [3]. Endoscopically assisted, minimally invasive decompression adequately and safely decompressed all anatomical points of compression and improved DASH scores for pronator syndrome [12]. Surgical decompression provides satisfactory outcomes for patients with persistent forearm pain and median nerve symptoms [32].

Complications

Nerve palsy: Median nerve palsy is a rare but potentially devastating complication of arthroscopic elbow contracture release [21]. In pronator syndrome, persistent symptoms for >6 months indicate surgical nerve decompression [1]. For anterior interosseous nerve syndrome (AINS), a minimum of 12 months with no signs of motor improvement warrants surgical decompression [1]. Concurrent carpal tunnel syndrome and pronator syndrome are rarely considered, leading to proximal compression sites being easily overlooked [8]. Median nerve compression can occur secondary to a high insertion of the pronator teres [10].

Diagnostic pitfalls: Evaluation of throwers with medial elbow pain requires a complete history and careful examination to avoid confirmation bias [5]. Fascicular constrictions typifying AINS were identified in all MRN cases [7] and in 88% of ultrasound cases [7]. These fascicular constrictions are predominantly located in the posterior/posteromedial region proximal to the elbow joint line [7]. The pathology originally described by Bennett should be termed chronic exertional compartment syndrome of the pronator teres or 'Bennett's syndrome' [18].

Recovery

Light activity (weeks): Specific time ranges for light activity, desk work, or driving are not provided in the current evidence base.

Full activity (months): Specific time ranges for manual work, sport, or full return of range of motion and strength are not provided in the current evidence base.

Complete recovery / outcome plateau (months): Specific time ranges for the stabilization of pain, strength, and final functional outcomes are not provided in the current evidence base.

Rehabilitation protocol: Specific rehabilitation protocols, including physical therapy phasing, immobilization duration, or weight-bearing progressions, are not provided in the current evidence base.

Functional milestones: Validated patient-reported outcome measure trajectories or specific benchmark values are not provided in the current evidence base.

Other Considerations: Clinical outcomes and anatomical findings relevant to recovery include the following: Pronator teres symptoms disappeared in 93% of cases following mini-invasive decompression technique [3]. The ulnar head of the pronator teres muscle is fibrotic or fibromuscular in 71.5% of cases [6]. Fascicular constrictions typifying anterior interosseous nerve syndrome were identified in all MRN cases and 88% of ultrasound cases [7]. Median nerve compression secondary to a high insertion of the pronator teres is associated with a supracondylar process [10]. Acute median nerve symptoms secondary to lacertus fibrosus syndrome can occur following distal biceps tendon repair [16]. Acute compression of the median nerve by a proximally displaced and tethered lacertus fibrosus causes dynamic compression [20]. Acute compression of the median nerve by the lacertus fibrosus is well treated by surgical release of the lacertus fibrosus [20]. Delayed-onset anterior interosseous nerve palsy can develop one week after open elbow contracture release, likely due to a stretch injury [22]. Resection of a segment of the persistent median artery is the recommended treatment for pronator syndrome associated with this anomaly [33].

Key Evidence

  • [Paper] Surgical indications for nerve decompression include persistent symptoms for >6 months in patients with pronator syndrome or for a minimum of 12 months with no signs of motor improvement in those with anterior interosseous nerve syndrome. [1] (10.5435/jaaos-21-05-268)
  • [L5] It is essential for clinicians to have a thorough understanding of median nerve anatomy, possible sites of compression, and characteristic clinical findings of pronator syndrome to provide a reliable diagnosis and treat their patients. [2] (10.1016/j.jhsa.2020.07.006)
  • [L4] Pronator teres symptoms disappeared in 93% of cases following the mini-invasive technique. [3] (10.1016/j.jhsa.2012.05.033)
  • [L5] The diagnosis of pronator syndrome lacks objective pathophysiology and is supported only by subjective operative findings and relief after surgery, with a paucity of controlled trials demonstrating that operative treatment is more effective than other treatments or sham surgery. [4] (10.1016/j.jhsa.2011.02.014)
  • [L5] It is important to take a complete history and perform a careful examination to avoid confirmation bias when evaluating throwers with medial elbow pain. [5] (10.1016/j.csm.2020.03.004)
  • [L5] The ulnar head of the pronator teres is fibrotic or fibromuscular in 71.5% of cases, and its morphology and location relative to the median nerve are important for surgical treatment of pronator syndrome. [6] (10.1016/j.otsr.2016.08.016)
  • [L4] These constrictions were identified in all MRN cases and 88% of ultrasound cases, predominantly in the posterior/posteromedial region proximal to the elbow joint line. [7] (10.1002/mus.26768)
  • [L4] Concurrent carpal tunnel syndrome and pronator syndrome are rarely considered and proximal compression sites are easily overlooked. [8] (10.1016/j.otsr.2016.10.009)
  • [L5] Lacertus syndrome and superficialis-pronator syndrome should be clearly presented as distinct targets for surgical release, and the term pronator syndrome should be replaced with superficialis-pronator syndrome. [9] (10.1177/17531934211024092)
  • [L4] [10] (10.1111/j.1758-5740.2010.00051.x)
  • [L4] The author is a proponent of the endoscopic technique with minimal damage and foresees its wide indication in the future for pronator syndrome. [11] (10.1177/17531934221076298)
  • [L4] The endoscopically assisted, minimally invasive approach to treat pronator syndrome adequately and safely decompressed all anatomical points of compression and improved DASH scores. [12] (10.1016/j.jhsa.2012.02.023)
  • [L5] Surgical decompression of the median nerve or the AIN in the forearm is rarely indicated; a prolonged nonsurgical approach is warranted in most cases. [13] (10.5435/jaaos-d-16-00010)
  • [L4] The diagnostic process to differentiate pronator syndrome from carpal tunnel syndrome remains a challenge due to overlapping symptoms and limited reliable information in the literature; this review provides a comprehensive clinical comparison to aid in establishing appropriate diagnosis and treatment. [14] (10.3390/diagnostics12102433)
  • [L4] With clinical evaluation as the reference standard, electrodiagnostic, ultrasound, and MRI are not helpful in making a diagnosis of pronator syndrome concurrent with carpal tunnel syndrome. [15] (10.1016/j.jhsa.2020.06.006)
  • [Case_report] This case presents a unique instance of median nerve symptoms secondary to lacertus fibrosus syndrome after distal biceps tendon repair. [16] (10.1016/j.xrrt.2024.08.009)
  • [L5] [17] (10.1016/j.jhsa.2009.10.017)
  • [L5] The authors recommend that the term 'lacertus syndrome' refer to intermittent median nerve compression at the level of the lacertus fibrosus, while the pathology originally described by Bennett should be termed chronic exertional compartment syndrome of the pronator teres or 'Bennett's syndrome' to resolve current terminology confusion. [18] (10.1177/17531934231170347)
  • [L4] An isolated anterior interosseous nerve injury may not by itself be an indication for urgent surgery. [19] (10.2106/jbjs.n.00136)
  • [L4] Acute compression of the median nerve from the proximally displaced and tethered lacertus fibrosus appears to cause the resultant dynamic compression of the median nerve and is well treated by surgical release of the lacertus fibrosus. [20] (10.1016/j.jse.2006.04.005)
  • [L4] We report a rare but possibly devastating complication of median nerve palsy after arthroscopic elbow contracture release. [21] (10.1016/j.jse.2019.06.003)
  • [Case_report] The authors describe a case of delayed-onset anterior interosseous nerve palsy developing one week after open elbow contracture release, likely due to a stretch injury. [22] (10.5397/cise.2022.00899)
  • [L4] [24] (10.1177/17531934251346595)
  • [L5] [26] (10.1016/j.jhsa.2010.08.018)
  • [L4] [27] (10.1177/1753193417726214)
  • [L4] The findings suggest that the function of the PT and PQ cannot be isolated by elbow flexion positioning. [29] (10.1016/j.jhsa.2025.09.013)
  • [L5] Compression of the anterior interosseous nerve by normal surrounding tissues may not exist or is very rare, with most cases likely representing neuritis; conservative treatment for at least 6 months is recommended before considering surgery. [30] (10.1177/17531934221074903)
  • [L4] Surgical decompression provides satisfactory outcomes for patients with persistent forearm pain and median nerve symptoms. [32] (10.1177/1558944719874137)
  • [Case_report] Resection of a segment of the persistent median artery is the recommended treatment for pronator syndrome associated with this anomaly. [33] (10.2106/00004623-198769020-00026)
  • [L4] Type 4 median nerve entrapment is a severe form of a rare complication of elbow dislocation. [34] (10.1007/s00402-003-0565-1)
  • [Paper] The study inventoried and mapped 6 potentially compressive structures neighboring or crossing the median nerve, showing precise proximal-to-distal locations with variations of 0.5 to 1.5 cm. [37] (10.1016/j.otsr.2021.102813)
  • [L5] A case of median nerve entrapment at the elbow by a non-osseous fibrous ligament (Struthers) is presented. [39] (10.3171/jns.1973.38.6.0778)
  • [L4] Details about the origin and course of the AIN can explain the high percentage of AIN palsy in supracondylar elbow fractures in children. [40] (10.1016/j.otsr.2013.04.002)

References

[1] Pronator Syndrome and Anterior Interosseous Nerve Syndrome. Journal of the American Academy of Orthopaedic Surgeons. 2013. DOI: 10.5435/jaaos-21-05-268

[2] Proximal Median Nerve Compression: Pronator Syndrome. The Journal of Hand Surgery. 2020. DOI: 10.1016/j.jhsa.2020.07.006

[3] New Mini-invasive Decompression for Pronator Teres Syndrome. The Journal of Hand Surgery. 2012. DOI: 10.1016/j.jhsa.2012.05.033

[4] Pronator Syndrome. The Journal of Hand Surgery. 2011. DOI: 10.1016/j.jhsa.2011.02.014

[5] The Lacertus Syndrome of the Elbow in Throwing Athletes. Clinics in Sports Medicine. 2020. DOI: 10.1016/j.csm.2020.03.004

[6] Morphology and morphometry of the ulnar head of the pronator teres muscle in relation to median nerve compression at the proximal forearm. Orthopaedics & Traumatology: Surgery & Research. 2016. DOI: 10.1016/j.otsr.2016.08.016

[7] Fascicular constrictions above elbow typify anterior interosseous nerve syndrome. Muscle & Nerve. 2019. DOI: 10.1002/mus.26768

[8] Concurrent carpal tunnel syndrome and pronator syndrome: A retrospective study of 21 cases. Orthopaedics & Traumatology: Surgery & Research. 2017. DOI: 10.1016/j.otsr.2016.10.009

[9] Median nerve compression: lacertus syndrome versus superficialis-pronator syndrome. Journal of Hand Surgery (European Volume). 2021. DOI: 10.1177/17531934211024092

[10] Median Nerve Compression Secondary to a High Insertion of Pronator Teres. Shoulder & Elbow. 2010. DOI: 10.1111/j.1758-5740.2010.00051.x

[11] Re: Tang JB. Median nerve compression: lacertus syndrome versus superficialis-pronator syndrome. J Hand Surg Eur. 2021, 46: 1017–22. Journal of Hand Surgery (European Volume). 2022. DOI: 10.1177/17531934221076298

[12] Endoscopically Assisted Decompression for Pronator Syndrome. The Journal of Hand Surgery. 2012. DOI: 10.1016/j.jhsa.2012.02.023

[13] Ulnar Tunnel Syndrome, Radial Tunnel Syndrome, Anterior Interosseous Nerve Syndrome, and Pronator Syndrome. Journal of the American Academy of Orthopaedic Surgeons. 2017. DOI: 10.5435/jaaos-d-16-00010

[14] How to Differentiate Pronator Syndrome from Carpal Tunnel Syndrome: A Comprehensive Clinical Comparison. Diagnostics. 2022. DOI: 10.3390/diagnostics12102433

[15] Clinical, Radiological, and Electrodiagnostic Diagnosis of Pronator Syndrome Concurrent With Carpal Tunnel Syndrome. The Journal of Hand Surgery. 2020. DOI: 10.1016/j.jhsa.2020.06.006

[16] Acute median nerve compression secondary to lacertus fibrosis syndrome following distal biceps tendon reconstruction: a case report. JSES Reviews, Reports, and Techniques. 2025. DOI: 10.1016/j.xrrt.2024.08.009

[17] Unusual Compression Neuropathies of the Forearm, Part II: Median Nerve. The Journal of Hand Surgery. 2009. DOI: 10.1016/j.jhsa.2009.10.017

[18] Lacertus syndrome: one term – two different pathologies. Journal of Hand Surgery (European Volume). 2023. DOI: 10.1177/17531934231170347

[19] Supracondylar Humeral Fractures with Isolated Anterior Interosseous Nerve Injuries: Is Urgent Treatment Necessary?. The Journal of Bone and Joint Surgery-American Volume. 2014. DOI: 10.2106/jbjs.n.00136

[20] Acute compression of the median nerve at the elbow by the lacertus fibrosus. Journal of Shoulder and Elbow Surgery. 2007. DOI: 10.1016/j.jse.2006.04.005

[21] High median nerve injury after arthroscopic elbow contracture release with complete recovery at 6 months. Journal of Shoulder and Elbow Surgery. 2019. DOI: 10.1016/j.jse.2019.06.003

[22] Anterior interosseous nerve palsy in the early postoperative period after open capsular release for elbow stiffness: a case report. Clinics in Shoulder and Elbow. 2023. DOI: 10.5397/cise.2022.00899

[24] Incidence of local tenderness at the lacertus fibrosus in healthy people. Journal of Hand Surgery (European Volume). 2025. DOI: 10.1177/17531934251346595

[26] Anterior Interosseous Nerve Syndrome. The Journal of Hand Surgery. 2010. DOI: 10.1016/j.jhsa.2010.08.018

[27] The scratch collapse test in the diagnosis of compression of the median nerve in the proximal forearm. Journal of Hand Surgery (European Volume). 2017. DOI: 10.1177/1753193417726214

[29] Rethinking Muscle Testing: Dynamic EMG Studies of Elbow Positioning as a Differentiator of Pronator Teres and Quadratus Functions. The Journal of Hand Surgery. 2026. DOI: 10.1016/j.jhsa.2025.09.013

[30] Compression to the anterior interosseous nerve is very rare: compression by the normal tissues surrounding it may not exist. Journal of Hand Surgery (European Volume). 2022. DOI: 10.1177/17531934221074903

[32] Median Nerve Compression in the Forearm: A Clinical Diagnosis. HAND. 2019. DOI: 10.1177/1558944719874137

[33] Pronator syndrome associated with a persistent median artery. A case report.. The Journal of Bone & Joint Surgery. 1987. DOI: 10.2106/00004623-198769020-00026

[34] Type 4 median nerve entrapment in a child after elbow dislocation. Archives of Orthopaedic and Trauma Surgery. 2003. DOI: 10.1007/s00402-003-0565-1

[37] Topographic anatomy of structures liable to compress the median nerve at the elbow and proximal forearm. Orthopaedics & Traumatology: Surgery & Research. 2021. DOI: 10.1016/j.otsr.2021.102813

[39] Struthers ligament: a source of median nerve compression above the elbow. Journal of Neurosurgery. 1973. DOI: 10.3171/jns.1973.38.6.0778

[40] The anatomical basis for anterior interosseous nerve palsy secondary to supracondylar humerus fractures in children. Orthopaedics & Traumatology: Surgery & Research. 2013. DOI: 10.1016/j.otsr.2013.04.002

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3. To the extent possible, the Licensor waives any right to collect royalties from You for the exercise of the Licensed Rights, whether directly or through a collecting society under any voluntary or waivable statutory or compulsory licensing scheme. In all other cases the Licensor expressly reserves any right to collect such royalties, including when the Licensed Material is used other than for NonCommercial purposes.

Section 3 -- License Conditions.

Your exercise of the Licensed Rights is expressly made subject to the following conditions.

a. Attribution.

1. If You Share the Licensed Material (including in modified form), You must:

a. retain the following if it is supplied by the Licensor with the Licensed Material:

i. identification of the creator(s) of the Licensed Material and any others designated to receive attribution, in any reasonable manner requested by the Licensor (including by pseudonym if designated);

ii. a copyright notice;

iii. a notice that refers to this Public License;

iv. a notice that refers to the disclaimer of warranties;

v. a URI or hyperlink to the Licensed Material to the extent reasonably practicable;

b. indicate if You modified the Licensed Material and retain an indication of any previous modifications; and

c. indicate the Licensed Material is licensed under this Public License, and include the text of, or the URI or hyperlink to, this Public License.

2. You may satisfy the conditions in Section 3(a)(1) in any reasonable manner based on the medium, means, and context in which You Share the Licensed Material. For example, it may be reasonable to satisfy the conditions by providing a URI or hyperlink to a resource that includes the required information.

3. If requested by the Licensor, You must remove any of the information required by Section 3(a)(1)(A) to the extent reasonably practicable.

4. If You Share Adapted Material You produce, the Adapter's License You apply must not prevent recipients of the Adapted Material from complying with this Public License.

Section 4 -- Sui Generis Database Rights.

Where the Licensed Rights include Sui Generis Database Rights that apply to Your use of the Licensed Material:

a. for the avoidance of doubt, Section 2(a)(1) grants You the right to extract, reuse, reproduce, and Share all or a substantial portion of the contents of the database for NonCommercial purposes only;

b. if You include all or a substantial portion of the database contents in a database in which You have Sui Generis Database Rights, then the database in which You have Sui Generis Database Rights (but not its individual contents) is Adapted Material; and

c. You must comply with the conditions in Section 3(a) if You Share all or a substantial portion of the contents of the database.

For the avoidance of doubt, this Section 4 supplements and does not replace Your obligations under this Public License where the Licensed Rights include other Copyright and Similar Rights.

Section 5 -- Disclaimer of Warranties and Limitation of Liability.

a. UNLESS OTHERWISE SEPARATELY UNDERTAKEN BY THE LICENSOR, TO THE EXTENT POSSIBLE, THE LICENSOR OFFERS THE LICENSED MATERIAL AS-IS AND AS-AVAILABLE, AND MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND CONCERNING THE LICENSED MATERIAL, WHETHER EXPRESS, IMPLIED, STATUTORY, OR OTHER. THIS INCLUDES, WITHOUT LIMITATION, WARRANTIES OF TITLE, MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT, ABSENCE OF LATENT OR OTHER DEFECTS, ACCURACY, OR THE PRESENCE OR ABSENCE OF ERRORS, WHETHER OR NOT KNOWN OR DISCOVERABLE. WHERE DISCLAIMERS OF WARRANTIES ARE NOT ALLOWED IN FULL OR IN PART, THIS DISCLAIMER MAY NOT APPLY TO YOU.

b. TO THE EXTENT POSSIBLE, IN NO EVENT WILL THE LICENSOR BE LIABLE TO YOU ON ANY LEGAL THEORY (INCLUDING, WITHOUT LIMITATION, NEGLIGENCE) OR OTHERWISE FOR ANY DIRECT, SPECIAL, INDIRECT, INCIDENTAL, CONSEQUENTIAL, PUNITIVE, EXEMPLARY, OR OTHER LOSSES, COSTS, EXPENSES, OR DAMAGES ARISING OUT OF THIS PUBLIC LICENSE OR USE OF THE LICENSED MATERIAL, EVEN IF THE LICENSOR HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH LOSSES, COSTS, EXPENSES, OR DAMAGES. WHERE A LIMITATION OF LIABILITY IS NOT ALLOWED IN FULL OR IN PART, THIS LIMITATION MAY NOT APPLY TO YOU.

c. The disclaimer of warranties and limitation of liability provided above shall be interpreted in a manner that, to the extent possible, most closely approximates an absolute disclaimer and waiver of all liability.

Section 6 -- Term and Termination.

a. This Public License applies for the term of the Copyright and Similar Rights licensed here. However, if You fail to comply with this Public License, then Your rights under this Public License terminate automatically.

b. Where Your right to use the Licensed Material has terminated under Section 6(a), it reinstates:

1. automatically as of the date the violation is cured, provided it is cured within 30 days of Your discovery of the violation; or

2. upon express reinstatement by the Licensor.

For the avoidance of doubt, this Section 6(b) does not affect any right the Licensor may have to seek remedies for Your violations of this Public License.

c. For the avoidance of doubt, the Licensor may also offer the Licensed Material under separate terms or conditions or stop distributing the Licensed Material at any time; however, doing so will not terminate this Public License.

d. Sections 1, 5, 6, 7, and 8 survive termination of this Public License.

Section 7 -- Other Terms and Conditions.

a. The Licensor shall not be bound by any additional or different terms or conditions communicated by You unless expressly agreed.

b. Any arrangements, understandings, or agreements regarding the Licensed Material not stated herein are separate from and independent of the terms and conditions of this Public License.

Section 8 -- Interpretation.

a. For the avoidance of doubt, this Public License does not, and shall not be interpreted to, reduce, limit, restrict, or impose conditions on any use of the Licensed Material that could lawfully be made without permission under this Public License.

b. To the extent possible, if any provision of this Public License is deemed unenforceable, it shall be automatically reformed to the minimum extent necessary to make it enforceable. If the provision cannot be reformed, it shall be severed from this Public License without affecting the enforceability of the remaining terms and conditions.

c. No term or condition of this Public License will be waived and no failure to comply consented to unless expressly agreed to by the Licensor.

d. Nothing in this Public License constitutes or may be interpreted as a limitation upon, or waiver of, any privileges and immunities that apply to the Licensor or You, including from the legal processes of any jurisdiction or authority.

Creative Commons is not a party to its public licenses. Notwithstanding, Creative Commons may elect to apply one of its public licenses to material it publishes and in those instances will be considered the “Licensor.” The text of the Creative Commons public licenses is dedicated to the public domain under the CC0 Public Domain Dedication. Except for the limited purpose of indicating that material is shared under a Creative Commons public license or as otherwise permitted by the Creative Commons policies published at creativecommons.org/policies, Creative Commons does not authorize the use of the trademark "Creative Commons" or any other trademark or logo of Creative Commons without its prior written consent including, without limitation, in connection with any unauthorized modifications to any of its public licenses or any other arrangements, understandings, or agreements concerning use of licensed material. For the avoidance of doubt, this paragraph does not form part of the public licenses.

Creative Commons may be contacted at creativecommons.org.