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British Journal of Pain logoLink to British Journal of Pain
. 2018 Sep 21;13(3):137–144. doi: 10.1177/2049463718800352

Up to a quarter of patients with certain chronic recalcitrant tendinopathies may have central sensitisation: a prospective cohort of more than 300 patients

Patrick C Wheeler 1,2,3,✉
PMCID: PMC6613072  PMID: 31308939

Abstract

Introduction:

To identify the possible prevalence of ‘central sensitisation’, in patients with chronic recalcitrant lower limb tendinopathy conditions, with the Central Sensitisation Inventory (CSI) questionnaire.

Methods:

Patients with chronic lower limb tendinopathy conditions treated within a single hospital outpatient clinic specialising in tendinopathy were identified from clinical records. As part of routine care, self-reported numerical markers of pain, global function (using the EuroQol-5D (EQ-5D) questionnaire) and the CSI score to investigate the possibility of central sensitisation were completed.

Results:

A total of 312 suitable patients with chronic lower limb tendinopathy and similar conditions were identified, who had completed a CSI questionnaire. Of these, 108 presented with greater trochanteric pain syndrome, 12 with patella tendinopathy, 33 with non-insertional Achilles tendinopathy, 48 with insertional Achilles tendinopathy and 110 with plantar fasciitis. A total of 66% of the patients were female, the median age was 54.9 years and the median duration of symptoms was 24 months. There was a median CSI score of 25%, with statistically significant differences noted between the different conditions studied. Overall, 20% of patients scored above a threshold of 40% on CSI questionnaire, indicating that central sensitisation was possible. Greater trochanteric pain syndrome and plantar fasciitis had the highest proportions in the conditions studied. Weak correlations were found between CSI and other pain scores studied.

Conclusion:

The CSI questionnaire may identify up to a quarter of patients with some chronic lower limb tendinopathy and associated conditions as being more likely to have central sensitisation, and these proportions differed between conditions. The clinical significance of this is unclear, but worth further study to see if/how this may relate to treatment outcomes. These are results from a single hospital clinic dealing with patients with chronic tendinopathy, and comparison with a control group is currently lacking. However, on the information presented here, the concept of central sensitisation should be considered in patients being treated for chronic tendinopathy.

Keywords: Tendinopathy, questionnaire, chronic pain, diagnosis, soft tissue

Introduction

Lower limb tendinopathy conditions are common causes of chronic musculoskeletal pain presenting to primary and secondary care. While many of these will improve over 12 months, about 10%–35% of patients can be left with ongoing symptoms that can have a significant impact on quality of life.1–3 This project focuses on four specific common lower limb tendinopathy, and ‘tendinopathy-like’, conditions and seeks to identify if patients with chronic tendon pain may have central sensitisation as a component of their pain symptoms which may contribute to the chronicity of their symptoms, through the use of the Central Sensitisation Inventory (CSI) questionnaire. These include patients with greater trochanteric pain syndrome (GTPS), patellar tendinopathy, Achilles tendinopathy (both insertional and non-insertional subtypes) and plantar fasciitis, all of which are discussed below.

Although subject to clinical debate, the ‘central sensitisation syndrome’ is postulated as a condition in which the central nervous system has become hypersensitive to both noxious and non-noxious stimuli with dysfunction of both ascending and descending pathways.4 This may be common in patients with chronic pain with a range of other diagnoses including chronic low back pain, osteoarthritis and fibromyalgia and which can potentially co-exist with those with structural pathology.4–8 Identification of patients with this condition could facilitate a more holistic pain management approach to their symptoms, potentially alongside other physical treatments. The CSI is a questionnaire with high reliability and validity in identifying patients thought to have this phenomenon; published work has shown that a score of more than 40 best distinguishes patients with/without central sensitisation.7–10 Further work comparing this questionnaire against experienced clinical assessment demonstrated that the CSI has a sensitivity of 83% and a specificity of 55%, but may have a high false-positive rate in patients with complex pain and medical conditions, and the authors concluded that this questionnaire was found to be a useful and valid instrument in screening patients for the possibility of central sensitisation.11

Classical lower limb tendinopathies that were studied in this project include those of the patella and the Achilles tendons. Two distinct anatomical locations of Achilles tendinopathy are described in the literature; the commoner site is in the mid-portion of the Achilles tendon with maximal pain and swelling occurring between 2 and 7 cm proximal to the calcaneal attachment and is often called ‘non-insertional’ (or mid-substance) tendinopathy.12 A less common subtype is the insertional tendinopathy which directly affects the insertion of the Achilles tendon into the posterior aspect of the calcaneus and is sometimes associated with an enlarged bursa.13 Patellar tendinopathy is a similar degenerative tendinopathy affecting the patella tendon, which is the terminal portion of the knee extensor mechanism group.14–16 The processes involved in the development of tendinopathy between these two, and other, sites are thought to be very similar.17,18 Other conditions studied here include GTPS and plantar fasciitis, both of which have great similarities in pathology, biomechanical properties and treatments to other classical tendinopathies.

Recent work in GTPS has looked beyond the trochanteric bursa being the primary source of pain and pathology and towards the insertion of the gluteal tendons, in particular gluteus medius, and which behaves and is treated in a similar way to other insertional tendinopathies.19–21 The plantar fascia is anatomically not strictly a tendinopathy, but behaves in a very similar way to one and is treated in a similar way to one. The plantar fascia is a band of connective tissue in the sole of the foot originating at the medial process of the tuberosity of the calcaneus and inserting in slips to the proximal phalanxes which has roles both in supporting the longitudinal arch of the foot and also in proprioception and peripheral motor coordination.22 The plantar fascia can develop a degenerative thickening process associated with pain similar to that seen in tendinopathies, called plantar fasciitis, with myxoid degeneration, associated with areas of proliferation of fibroblasts and increased vascularity.23–26 Its insertion into bone is very similar to that of an insertional tendon, its degenerative processes are similar to those seen in an established tendinopathy and the effective treatments used are very similar to those in tendinopathy management. Therefore, for the purposes of this review will be considered similar, if not the same, as a classical tendinopathy, although the challenges of this approach are recognised.

GTPS, Achilles tendinopathy and plantar fasciitis are all common conditions; both GTPS and Achilles tendinopathy have an incidence of about 1.8–2.3/1000 adults, and there may be a lifetime risk of 10% of developing plantar fasciitis.2,26,27 These conditions most commonly affect people between 40 and 60, affect women slightly more than men and have a wide range of risk factors including activity, or lack thereof, obesity, impaired lower limb flexibility and multiple genetic factors.19–30 Patellar tendinopathy is less common in sedentary populations than other tendon conditions, is associated most with individuals particularly involved in sports with sprinting or jumping/landing components and has been previously known as ‘jumper’s knee’.15,31 Patellar tendinopathy more commonly affects younger populations than some other tendon conditions, with athletes in one study having a mean onset of patellar tendinopathy symptoms at age 23.8 years (range 16–47).32

The underlying pathology of tendinopathies has been extensively studied over many years, with hypotheses moving away from a primarily inflammation-driven pathology (aka ‘tendinitis’) to a degenerative/mechanical ‘failed-healing’ model;18,33,34 however, recent work has shown that inflammatory processes remain involved within the entity of ‘tendinopathy’, particularly in the early stages.35,36 A wide range of treatment options are available to treat these conditions, which conceptually address nociceptive pain as well as functional impairment. Depending on the tendon location, these may include tension night splints (TNS),37–40 guided injections – including high-volume image-guided injections (HVIGIs)41,42 or autologous blood injections (ABIs),43–45 extracorporeal shockwave therapy (ESWT)46–48 or surgery in recalcitrant cases.49–51

It is believed that neuronal regulation has a vital role in tendon homeostasis, and the presence of neuropathic pain in chronic tendinopathies has been proposed.52,53 Vasculo-neural ingrowth into chronic tendinopathy is recognised has been proposed as a cause of pain, with tendinopathy associated with a local increase in a range of neurotransmitters including glutamate, as well as an increase in substance P–positive nerve fibres; however, mixed results have been found and no consistent answer is yet identified.54–57 Previous clinical work has suggested that more than a quarter of patients with chronic, recalcitrant lower limb tendinopathies scored highly on the painDETECT questionnaire which rates the likelihood of neuropathic pain.58 While this is not truly diagnostic of neuropathic pain, there is a consideration that many patients with chronic pain from a range of sources, including possibly tendinopathy, have pain that is not simply nociceptive in origin.

This project therefore seeks to identify if patients with chronic tendon pain may have central sensitisation as a component of their pain symptoms, through the use of the CSI questionnaire.

Methods

Procedural logs were examined from a single UK hospital outpatient clinic, which has a regional reputation for the management of patients with chronic tendinopathy. Patients that had been referred with a chronic lower limb tendinopathy/tendon-like condition, including GTPS, patella tendinopathy, Achilles tendinopathy (both insertional and non-insertional subtypes) and plantar fasciitis were identified. The treatments that these patients were to undertake included TNS devices, ESWT, HVIGIs or ABIs. The diagnosis of the condition was made by a single National Health Service (NHS) consultant, who specialises in musculoskeletal conditions and whose patient case mix is heavily slanted towards patients with pain from chronic tendinopathy, on the basis of clinical assessment, the exclusion of other differential diagnoses and the use of investigation modalities. All patients had symptoms that had failed to settle with simple conservative therapies, including a structured home rehabilitation programme.

Prior to the treatments and as a part of their routine care, patients completed baseline questionnaires about their pain and level of functioning, including a 0–10 self-rated value of their ‘average pain’, their ‘worst pain’ and their ‘average stiffness’. In addition, specific validated questionnaires including the CSI questionnaire9–11 to examine possible central sensitisation, and also the five-level EuroQol-5D version (EQ-5D-5L) questionnaire59,60 as a marker of global health and functioning, were also completed by the patient. Data were available for the period from 25 November 2015 to 13 November 2017, which were identified and transcribed by the author for analysis in this project.

Statistical analysis

Anonymised data from the procedural logs were inputted into a bespoke Excel spreadsheet (MS Excel for Mac 2011 – current version 15.39) by the author. All data were anonymised prior to analysis and held/used in accordance to hospital Trust procedures. From this, group values (including means, standard deviations, medians and ranges) were calculated for the patient group as a whole, and also for different conditions as subgroups. The majority of data collected (age, numerical rating scales and CSI) were scale data. This information was analysed through SPSS (v22) and the Shapiro–Wilk test was performed to assess normality. The majority of the data were found not to be normally distributed, and therefore non-parametric testing was used, typically independent-samples Mann–Whitney U, Kruskal–Wallis or Pearson chi-square tests as appropriate, with Spearman’s correlation used to assess the relationships between variables. Statistical significance was set at p < 0.05.

Ethical approvals

This project utilised anonymised data from questionnaires that patients who attended this outpatient department completed as a part of their routine clinical care. Patients were advised that these questions were designed to better understand their pain and the impact that their symptoms had on their quality of life and they were free to choose not to complete the questionnaires if they so wished. This specific project, which compares anonymised data across different conditions, is a part of a wider ongoing body of work examining different aspects of chronic tendinopathy which is fully registered with the hospital Trust and authorities. This specific project does not fulfil the criteria of research as stipulated by Health Research Authority (HRA) and specific formalised ethics approvals were not required for this project.

Results

Results were available for a total of 312 consecutive patients who attended this hospital clinic for specialised treatments for their lower limb tendinopathy/tendon-like conditions and who had completed the CSI questionnaire. All data collected were from November 2015 to November 2017. All patients had their diagnosis confirmed on imaging, typically ultrasound or magnetic resonance imaging (MRI). Results were available for 109 patients with GTPS, 12 patients with patella tendinopathy, a total of 81 patients with Achilles tendinopathy (of which 33 had non-insertional and 48 had insertional tendinopathy, who are listed separately hereafter) and 110 patients with plantar fasciitis.

The age range for the patients was between 23.7 and 88.6 years; 66% of patients were female and 34% were male. The duration of pre-existing symptoms ranged from 2 months to 30 years, and all patients had previously undertaken a rehabilitation programme of exercises. The patient demographics for each condition are displayed in Table 1; as the data are not normally distributed, the median values and interquartile ranges (IQRs) are displayed.

Table 1.

Patient demographics.

Age (years) Gender (%male/female) Duration of symptoms (months)
All patients (n = 312) 54.9 (46.4–88.6) 34/66 24.0 (12.0–36.0)
Greater trochanteric pain syndrome (n = 108) 62.1 (52.5–88.6) 20/80 24.0 (15.0–360.0)
Patella tendinopathy (n = 12) 35.5 (26.2–48.1) 83/17 18.0 (12.5–120.0)
Non-insertional Achilles tendinopathy (n = 33) 49.9 (45.1–68.7) 42/58 15.0 (12.0–84.0)
Insertional Achilles tendinopathy (n = 48) 57.1 (47.5–75.0) 44/56 18.0 (12.0–120.0)
Plantar fasciitis (n = 110) 50.4 (44.6–79.9) 35/65 24.0 (15.0–240.0)
*p < 0.001 *p < 0.001 *p = 0.003
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Data are presented as median (IQR).

*

indicates a statistically significant result (i.e. p < 0.05).

As highlighted in Table 1, these demographic variables differed significantly between the different conditions studied: age (p < 0.001), gender (p < 0.001) and duration of symptoms (p = 0.003), which was predominately explained by the differences seen from the group with patellar tendinopathy, compared to the remainder of the conditions studied. There was a weak, but statistically significant correlation between the CSI score and the duration of symptoms (rs = 0.217, p < 0.001), but not patient age (p = 0.137).

Self-reported pain and function scores

There were a median (IQR) overall self-reported ‘average pain’ of 7.0/10 (IQR: 5.0–10.0), a ‘worst pain’ score of 8.0/10 (IQR: 7.0–10.0) and a self-reported ‘average stiffness’ rating of 5.0/10 (IQR: 3.0–10.0). There were a median value of 71% (IQR: 60%–100%) scored on the EQ-5D global health percentage scale and a median CSI score of 25% (IQR: 14%–78%) for the patients studied. As the data were not normally distributed, the median values (and IQRs) for each of these measures are displayed in Table 2, with the significance of differences in variables between groups indicated.

Table 2.

Self-reported measures.

Self-reported ‘average pain’ (0–10) Self-reported ‘worst pain’ (0–10) Self-reported ‘average stiffness’ (0–10) EQ-5D (%health score) CSI score (%)
All patients (n = 312) 7.0 (5.0–10.0) 8.0 (7.0–10.0) 5.0 (3.0–10.0) 71 (60–100) 25 (14–78)
Greater trochanteric pain syndrome (n = 108) 6.3 (5.0–10.0) 8.0 (7.0–10.0) 5.0 (3.0–9.5) 71 (60–100) 29 (20–78)
Patella tendinopathy (n = 12) 7.0 (5.4–9.0) 8.3 (7.0–9.5) 4.3 (0.9–9.0) 71 (70–92) 17 (5–38)
Non-insertional Achilles tendinopathy (n = 33) 7.0 (5.0–9.0) 8.0 (5.0–9.0) 6.0 (4.0–9.0) 70 (60–99) 20 (14–52)
Insertional Achilles tendinopathy (n = 48) 5.5 (4.9–10.0) 7.5 (6.9–10.0) 5.0 (3.4–9.0) 72 (58–95) 22 (13–47)
Plantar fasciitis (n = 110) 7.0 (6.0–10.0) 8.8 (7.5–10.0) 6.0 (3.0–10.0) 70 (59–100) 27 (14–63)
Significance of differences between groups *p = 0.003 *p = 0.005 p = 0.126 p = 0.901 *p = 0.002
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EQ-5D: EuroQol-5D; CSI: Central Sensitisation Inventory.

Data are presented as median (IQR).

*

indicates a statistically significant result (i.e. p < 0.05).

The self-reported rating for ‘average stiffness’ and the EQ-5D %health score did not differ significantly between the different conditions (p = 0.126 and p = 0.901, respectively), but there were significant differences between the conditions for the other parameters studied including the values for ‘average pain’ (p = 0.003) and worst pain (p = 0.005). The median value for CSI in patients with patellar tendinopathy was 17%, compared to that in patients with GTPS of 29%, and those with plantar fasciitis of 27%. These differences between groups in the CSI score was statistically significant (p = 0.002). These values are displayed in Table 2.

There were no gender differences found between any of the variables studied except for the CSI value, which had a median (IQR) of 20% (IQR: 13%–78%) for the 106 male patients studied and 28% (IQR: 19%–28%) for the 206 female patients studied (p < 0.001). However, this may have been influenced by the different proportions of male/female patients with different conditions, as when the subgroups were analysed this difference was found to be non-significant and appears to be at least partially confounded by different proportions of male/female patients with the different conditions studied.

There were statistically significant, although weak-level, correlations found between the CSI score and the other variables studied, including the self-reported ‘average pain’ score (rs = 0.161, p = 0.004), ‘worst pain’ (rs = 0.216, p < 0.001), ‘average stiffness’ (rs = 0.266, p < 0.001) and the %health score of EQ-5D (rs = –0.386, p < 0.001).

Possible presence of central sensitisation

A CSI score above 40% has been suggested from the published literature to best identify those who are most likely to have central sensitisation; however, a high false-positive rate is noted giving a noted limitation to this approach.7,9–11 In this prospective study, a total of 19.6% of all subjects met this threshold, with variability apparent between different conditions. The condition with the highest proportion of scores above this threshold was GTPS with 25.9% subjects identified, and the next was plantar fasciitis with 23.6%; however, none of the subjects with patella tendinopathy scored above this threshold in this series. The proportion of those scoring over the 40% threshold on the CSI questionnaire is displayed in Table 3.

Table 3.

Proportion of patients scoring above 40% threshold on CSI score.

Proportion of subjects with CSI score above 40%
All (n = 312) 19.6%
Greater trochanteric pain syndrome (n = 108) 25.9%
Patella tendinopathy (n = 12) 0%
Non-insertional Achilles tendinopathy (n = 33) 6.1%
Insertional Achilles tendinopathy (n = 48) 10.4%
Plantar fasciitis (n = 110) 23.6%
*p = 0.011
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CSI: Central Sensitisation Inventory.

*

indicates a statistically significant result (i.e. p < 0.05).

‘Classical’ tendinopathies (such as non-insertional Achilles tendinopathy and patella tendinopathy) had lower prevalence levels than the other studied conditions (GTPS and plantar fasciitis) using this cut-off value. This difference reached statistical significance (p = 0.011), and the clinical significance of this remains uncertain.

There was no statistical difference found when directly comparing only those with non-insertional and insertional Achilles tendinopathy (p = 0.493), nor when comparing those with insertional Achilles tendinopathy (attaching to the posterior of the calcaneus) with those with plantar fasciitis (attachment on the under-surface of the calcaneus) (p = 0.054).

Discussion

This is a pragmatic project which investigated the possible prevalence of central sensitisation in patients presenting with a range of recalcitrant lower limb tendinopathy and similar conditions to this single outpatient department for further treatment. This project has shown that in some conditions a quarter of patients score highly enough on the CSI questionnaire to raise the possibility of central sensitisation. There were statistically significant differences found in this prevalence between different conditions; however, the reasons for this, and any clinical significance of this, remain unknown at this time. The study had limited numbers in some sub-population groups (notably patellar tendinopathy) and this is a noted limitation of this data set.

The CSI questionnaire has been shown to be a useful and valid instrument in screening patients for the possibility of central sensitisation in hospital outpatient departments.7,9–11 However, the high false-positive rate means that the information presented here must be treated with some reservations and may have given an artificially high prevalence figure, although there remains no alternative validated patient-reported outcome measure (PROM) to assess this concept. Irrespective of this, the statistically significant difference in point prevalence rates between different conditions of those scoring more than 40% on the CSI, which has been used as a threshold to determine those most likely to have a component of central sensitisation, is of interest and would be worthy of further study. In addition, as there were only weak correlations identified between the CSI and the other markers studied, it is suggested that these may be measuring different aspects of function, and the CSI may be useful in the global assessment of patients, without too great an overlap with other aspects presented here.

It is important to highlight that the clinical population studied here was not necessarily typical of the general population suffering from lower limb tendinopathy and was instead a population that was often resistant to previous treatments with the majority having symptoms for at least 2 years. It is unclear from these data whether the patients may have been resistant to other treatments due to the presence of a possible central sensitisation (as recorded by the CSI score), whether this may have developed due to the chronicity of the symptoms or if the two are unrelated. There was only a weak correlation found between the CSI and the duration of symptoms, but this did reach statistical significance. Therefore, this domain should be considered in future research, with a longitudinal study from early onset of symptoms being best placed to examine this.

Finally, the clinical significance of those scoring highly on the CSI questionnaire remains unclear. There was only a weak statistical correlation between the CSI and the patient’s self-reported ‘average’ or ‘worst’ levels of pain, indicating that this did not just identify patients with the most problematic symptoms. Instead, this may have identified those patients in which factors other than purely nociceptive pain may be involved. If this is the case, then further work could examine whether the CSI is of value as a prognostic factor in the response to treatments, and if so could be of value in determining an individualised pathway of care.

Conclusion

In summary, the CSI is a patient-rated questionnaire that may have some application in the management of patients with recalcitrant lower limb tendinopathies. This study suggests that up to a quarter of patients with some lower limb conditions score highly enough to be suggestive of central sensitisation being present, based on an identified threshold score from previously published work. There was a weak correlation found between the CSI score and the duration of symptoms, and also weak correlations between the CSI and other markers of patient pain/function. However, the clinical implications of these CSI scores in this clinical population remain unclear at this time and are in need of further research.

Acknowledgments

The author would like to offer his thanks to the patients that have been involved in this project and also to his colleagues who have helped the author in various ways in various different projects. This manuscript has a single author. This author was responsible for collecting, collating and analysing the results and writing the manuscript. P.C.W. is the guarantor of this article.

Footnotes

Conflict of interest: The author(s) declared no potential conflicts of interest with respect to the research, authorship and/or publication of this article.

Ethical approval: HRA/University Hospitals of Leicester NHS Trust does not require ethical approval for reporting individual cases or case series.

Funding: The author(s) received no financial support for the research, authorship and/or publication of this article.

Informed consent: Written informed consent was obtained from all subjects before the study.

ORCID iD: Patrick C Wheeler Inline graphic https://orcid.org/0000-0003-2509-9767

References

  • 1. Paavola M, Kannus P, Paakkala T, et al. Long-term prognosis of patients with Achilles tendinopathy: an observational 8-year follow-up study. Am J Sports Med 2000; 28(5): 634–642. [DOI] [PubMed] [Google Scholar]
  • 2. Lievense A, Bierma-Zeinstra S, Schouten B, et al. Prognosis of trochanteric pain in primary care. Br J Gen Pract 2005; 55(512): 199–204. [PMC free article] [PubMed] [Google Scholar]
  • 3. DiGiovanni BF, Nawoczenski DA, Lintal ME, et al. Tissue-specific plantar fascia-stretching exercise enhances outcomes in patients with chronic heel pain. A prospective, randomized study. J Bone Joint Surg Am 2003; 85-A(7): 1270–1277. [DOI] [PubMed] [Google Scholar]
  • 4. Kindler LL, Bennett RM, Jones KD. Central sensitivity syndromes: mounting pathophysiologic evidence to link fibromyalgia with other common chronic pain disorders. Pain Manag Nurs 2011; 12(1): 15–24. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 5. Holm LW, Carroll LJ, Cassidy JD, et al. Widespread pain following whiplash-associated disorders: incidence, course, and risk factors. J Rheumatol 2007; 34(1): 193–200. [PubMed] [Google Scholar]
  • 6. Aggarwal VR, McBeth J, Zakrzewska JM, et al. The epidemiology of chronic syndromes that are frequently unexplained: do they have common associated factors? Int J Epidemiol 2006; 35(2): 468–476. [DOI] [PubMed] [Google Scholar]
  • 7. Nijs J, Torres-Cueco R, van Wilgen P, et al. Applying modern pain neuroscience in clinical practice: criteria for the classification of central sensitization pain. Pain Physician 2014; 17(5): 447–457. [PubMed] [Google Scholar]
  • 8. Lluch E, Torres R, Nijs J, et al. Evidence for central sensitization in patients with osteoarthritis pain: a systematic literature review. Eur J Pain 2014; 18: 1367–1375. [DOI] [PubMed] [Google Scholar]
  • 9. Mayer TG, Neblett R, Cohen H, et al. The development and psychometric validation of the Central Sensitization Inventory. Pain Pract 2012; 12(4): 276–285. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 10. Neblett R, Cohen H, Choi Y, et al. The Central Sensitization Inventory (CSI): establishing clinically significant values for identifying central sensitivity syndromes in an outpatient chronic pain sample. J Pain 2013; 14(5): 438–445. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 11. Neblett R, Hartzell MM, Cohen H, et al. Ability of the Central Sensitization Inventory to identify central sensitivity syndromes in an outpatient chronic pain sample. Clin J Pain 2015; 31(4): 323–332. [DOI] [PubMed] [Google Scholar]
  • 12. Alfredson H, Cook JL. A treatment algorithm for managing Achilles tendinopathy: new treatment options. Br J Sports Med 2007; 41(4): 211–216. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 13. Cook JL, Purdam C. Is compressive load a factor in the development of tendinopathy? Br J Sports Med 2012; 46(3): 163–168. [DOI] [PubMed] [Google Scholar]
  • 14. Cook JL, Khan KM. What is the most appropriate treatment for patellar tendinopathy? Br J Sports Med 2001; 35(5): 291–294. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 15. Peers KE, Lysens RJ. Patellar tendinopathy in athletes: current diagnostic and therapeutic recommendations. Sports Med 2005; 35(1): 71–87. [DOI] [PubMed] [Google Scholar]
  • 16. Helland C, Bojsen-Møller J, Raastad T, et al. Mechanical properties of the patellar tendon in elite volleyball players with and without patellar tendinopathy. Br J Sports Med 2013; 47(13): 862–868. [DOI] [PubMed] [Google Scholar]
  • 17. Sharma P, Maffulli N. Tendon injury and tendinopathy: healing and repair. J Bone Joint Surg Am 2005; 87(1): 187–202. [DOI] [PubMed] [Google Scholar]
  • 18. Cook JL, Purdam CR. Is tendon pathology a continuum? A pathology model to explain the clinical presentation of load-induced tendinopathy. Br J Sports Med 2009; 43(6): 409–416. [DOI] [PubMed] [Google Scholar]
  • 19. Williams BS, Cohen SP. Greater trochanteric pain syndrome: a review of anatomy, diagnosis and treatment. Anesth Analg 2009; 108(5): 1662–1670. [DOI] [PubMed] [Google Scholar]
  • 20. Kingzett-Taylor A, Tirman PF, Feller J, et al. Tendinosis and tears of gluteus medius and minimus muscles as a cause of hip pain: MR imaging findings. Am J Roentgenol 1999; 173(4): 1123–1126. [DOI] [PubMed] [Google Scholar]
  • 21. Silva F, Adams T, Feinstein J, et al. Trochanteric bursitis: refuting the myth of inflammation. J Clin Rheumatol 2008; 14(2): 82–86. [DOI] [PubMed] [Google Scholar]
  • 22. Stecco C, Corradin M, Macchi V, et al. Plantar fascia anatomy and its relationship with Achilles tendon and paratenon. J Anat 2013; 223(6): 665–676. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 23. Lemont H, Ammirati KM, Usen N. Plantar fasciitis: a degenerative process (fasciosis) without inflammation. J Am Podiatr Med Assoc 2003; 93(3): 234–237. [DOI] [PubMed] [Google Scholar]
  • 24. Drew BT, Smith TO, Littlewood C, et al. Do structural changes (eg, collagen/matrix) explain the response to therapeutic exercises in tendinopathy: a systematic review. Br J Sports Med 2014; 48: 966–972. [DOI] [PubMed] [Google Scholar]
  • 25. Rathleff MS, Thorborg K. ‘Load me up, Scotty’: mechanotherapy for plantar fasciopathy (formerly known as plantar fasciitis). Br J Sports Med 2015; 49: 638–639. [DOI] [PubMed] [Google Scholar]
  • 26. Orchard J. Plantar fasciitis. BMJ 2012; 345: e6603. [DOI] [PubMed] [Google Scholar]
  • 27. De Jonge S, van den Berg C, de Vos RJ, et al. Incidence of midportion Achilles tendinopathy in the general population. Br J Sports Med 2011; 45(13): 1026–1028. [DOI] [PubMed] [Google Scholar]
  • 28. Rompe JD, Segal NA, Cacchio A, et al. Home training, local corticosteroid injection, or radial shock wave therapy for greater trochanter pain syndrome. Am J Sports Med 2009; 37(10): 1981–1990. [DOI] [PubMed] [Google Scholar]
  • 29. Buchbinder R. Plantar fasciitis. New Engl J Med 2004; 350(21): 2159–2166. [DOI] [PubMed] [Google Scholar]
  • 30. Alfredson H. Chronic midportion Achilles tendinopathy: an update on research and treatment. Clin Sports Med 2003; 22(4): 727–741. [DOI] [PubMed] [Google Scholar]
  • 31. Lian ØB, Engebretsen L, Bahr R. Prevalence of jumper’s knee among elite athletes from different sports: a cross-sectional study. Am J Sports Med 2005; 33(4): 561–567. [DOI] [PubMed] [Google Scholar]
  • 32. Cook JL, Khan KM, Harcourt PR, et al. A cross sectional study of 100 athletes with jumper’s knee managed conservatively and surgically. The Victorian Institute of Sport Tendon Study Group. Br J Sports Med 1997; 31(4): 332–336. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 33. Abate M, Silbernagel KG, Siljeholm C, et al. Pathogenesis of tendinopathies: inflammation or degeneration? Arthritis Res Ther 2009; 11: 235. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 34. Rio E, Moseley L, Purdam C, et al. The pain of tendinopathy: physiological or pathophysiological? Sports Med 2014; 44(1): 9–23. [DOI] [PubMed] [Google Scholar]
  • 35. D’Addona A, Maffulli N, Formisano S, et al. Inflammation in tendinopathy. Surgeon 2017; 15(5): 297–302. [DOI] [PubMed] [Google Scholar]
  • 36. Millar NL, Murrell GAC, McInnes IB. Inflammatory mechanisms in tendinopathy – towards translation. Nat Rev Rheumatol 2017; 13: 110–122. [DOI] [PubMed] [Google Scholar]
  • 37. Lee WCC, Wong WY, Kung E, et al. Effectiveness of adjustable dorsiflexion night splint in combination with accommodative foot orthosis on plantar fasciitis. J Rehabil Res Dev 2012; 49(10): 1557–1564. [DOI] [PubMed] [Google Scholar]
  • 38. Wheeler PC. The effectiveness and tolerability of tension night splints for patients with chronic plantar fasciitis – a case-series study. Int Musculoskelet Med 2014; 36(4): 130–136. [Google Scholar]
  • 39. Landorf KB. Plantar heel pain and plantar fasciitis. BMJ Clin Evid, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4661045/ [PMC free article] [PubMed]
  • 40. Wheeler PC. The addition of a Tension Night Splint to a structured home rehabilitation programme in patients with chronic plantar fasciitis does not lead to significant additional benefits in either pain, function or flexibility: a single-blinded randomised controlled trial. BMJ Open Sport Exerc Med 2017; 3: e000234. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 41. Wheeler PC. The use of high-volume image-guided injections (HVIGI) for Achilles tendinopathy – a case series & pilot study. Int Musculoskelet Med 2014; 36(3): 96–103. [Google Scholar]
  • 42. Wheeler PC, Mahadevan D, Bhatt R, et al. A comparison of two different high-volume image-guided injection procedures for patients with chronic non-insertional Achilles tendinopathy: a pragmatic retrospective cohort study. J Foot Ankle Surg 2016; 55(5): 976–979. [DOI] [PubMed] [Google Scholar]
  • 43. Wheeler PC. Autologous blood injections for chronic plantar fasciitis – a pilot case-series study shows promising results. Int Musculoskelet Med 2013; 35(1): 3–7. [Google Scholar]
  • 44. Gross CE, Hsu AR, Chahal J, et al. Injectable treatments for noninsertional Achilles tendinosis: a systematic review. Foot Ankle Int 2013; 34(5): 619–628. [DOI] [PubMed] [Google Scholar]
  • 45. Wheeler PC. The role of autologous blood injections in the treatment for patients with chronic plantar fasciitis – a case series and longer term follow-up. Int Musculoskelet Med 2015; 37(2): 47–53. [Google Scholar]
  • 46. Mani-Babu S, Morrissey D, Waugh C, et al. The effectiveness of extracorporeal shock wave therapy in lower limb tendinopathy: a systematic review. Am J Sports Med 2015; 43(3): 752–761. [DOI] [PubMed] [Google Scholar]
  • 47. Wheeler PC, Tattersall C. The role of extra-corporeal shockwave therapy (ESWT) plus rehabilitation for patients with chronic greater trochanteric pain syndrome (GTPS), a case series assessing effects on pain, sleep quality, activity and functioning. Int Musculoskelet Med 2016; 38(1): 27–35. [Google Scholar]
  • 48. Wheeler PC, Tattersall C. Extracorporeal shockwave therapy plus rehabilitation for patients with chronic plantar fasciitis might reduce pain and improve function but still not lead to increased activity: a case-series study with multiple outcome measures. J Foot Ankle Surg 2018; 57(2): 339–345. [DOI] [PubMed] [Google Scholar]
  • 49. Wheeler PC, Boyd K, Shipton M. Surgery for patients with recalcitrant plantar fasciitis: good results at short-, medium-, and long-term follow-up. Orthop J Sport Med 2014; 2(3): 2325967114527901. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 50. Wiegerinck JI, Kerkhoffs GM, van Sterkenburg MN, et al. Treatment for insertional Achilles tendinopathy: a systematic review. Knee Surg Sport Tr A 2013; 21(6): 1345–1355. [DOI] [PubMed] [Google Scholar]
  • 51. Voos JE, Rudzki JR, Shindle MK, et al. Arthroscopic anatomy and surgical techniques for peritrochanteric space disorders in the hip. Arthroscopy 2007; 23(11): 1246.e1–1246.e5. [DOI] [PubMed] [Google Scholar]
  • 52. Webborn ADJ. Novel approaches to tendinopathy. Disabil Rehabil 2008; 30(20–22): 1572–1577. [DOI] [PubMed] [Google Scholar]
  • 53. Ackermann PW. Neuronal regulation of tendon homoeostasis. Int J Exp Pathol 2013; 94(4): 271–286. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 54. Alfredson H, Öhberg L, Forsgren S. Is vasculo-neural ingrowth the cause of pain in chronic Achilles tendinosis? An investigation using ultrasonography and colour Doppler, immunohistochemistry, and diagnostic injections. Knee Surg Sport Tr A 2003; 11(5): 334–338. [DOI] [PubMed] [Google Scholar]
  • 55. Alfredson H, Forsgren S, Thorsen K, et al. Glutamate NMDAR1 receptors localised to nerves in human Achilles tendons. Implications for treatment? Knee Surg Sport Tr A 2001; 9(2): 123–126. [DOI] [PubMed] [Google Scholar]
  • 56. Schubert TEO, Weidler C, Lerch K, et al. Achilles tendinosis is associated with sprouting of substance P positive nerve fibres. Ann Rheum Dis 2005; 64(7): 1083–1086. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 57. Alfredson H, Lorentzon R. Chronic tendon pain: no signs of chemical inflammation but high concentrations of the neurotransmitter glutamate. Implications for treatment? Curr Drug Targets 2002; 3(1): 43–54. [DOI] [PubMed] [Google Scholar]
  • 58. Wheeler PC. Neuropathic pain may be common in chronic lower limb tendinopathy: a prospective cohort study. Br J Pain 2017; 11(1): 16–22. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 59. Janssen MF, Pickard AS, Golicki D, et al. Measurement properties of the EQ-5D-5L compared to the EQ-5D-3L across eight patient groups: a multi-country study. Qual Life Res 2013; 22(7): 1717–1727. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 60. Herdman M, Gudex C, Lloyd A, et al. Development and preliminary testing of the new five-level version of EQ-5D (EQ-5D-5L). Qual Life Res 2011; 20(10): 1727–1736. [DOI] [PMC free article] [PubMed] [Google Scholar]

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