Sport and Exercise Medicine: The UK trainee perspective –A BJSM blog series

By Dr Farrah Jawad

Orthopaedic Research UK arranged a one-day Tendinopathy conference in London last week – Tendinopathy: state of play. The event brought together field leaders from sports and exercise medicine, physiotherapy and surgery “to address tendinopathy from the cellular level to the sporting arena.” It aimed to share the latest research and encourage discussion among clinicians.

Here are some key findings, highlighted in the speaker presentations.

Epidemiology of Achilles Tendinopathy in UK runners and the role of soleus in tendinopathy and rehabilitation – Mr Seth O’Neill, Physiotherapy Lecturer, Department of Medical and Social Care Education, University of Leicester

• Calf stretching may make the tendon-muscle unit more pliable
• Healthy controls seem to have less pliable tendons (cause or effect?)
• Soleus is very important in the running population as it contributes a large force during this activity. Its strength can reduce with age, which may be implicated in the onset of tendinopathy.
• Plantarflexor weakness has been demonstrated in Achilles tendinopathy patients
• Plantarflexion function and mechanistic studies may be targets for interventional studies.
• The contralateral limb should not be used in studies as a comparison to the tendinopathic side, as it is not an adequate control.

Tendon Loading and Implications for Injury – Dr Steve Pearson, Senior Lecturer in Human and Applied Physiology, University of Salford

• Potential mechanisms of tendinopathy may include: tendon overload or underload (these terms are difficult to define as they mean different things to different individuals), poor mechanics, insufficient recovery
• The superficial region of the Achilles tendon tends to undergo greater strain compared to the deep region – could this result in tendon maladaptation?
• It is possible that the increased water in tendinopathic tendons has a protective effect.
• Time under tension may be the most important factor in rehabilitation.
• Eccentric loading has shown benefits over other tendon loading protocols for clinical outcomes but not necessarily tendon structure.

Can new ultrasound imaging modalities influence the management of Achilles Tendinopathy? – Dr Bhavesh Kumar, Consultant in Sport and Exercise Medicine, Institute of Sport, Exercise and Health, University College London

• The limitations of ultrasound for tendons are that: hypoechoic areas can be difficult to delineate, ultrasound may be operator dependent and distinguishing between tears and tendinosis can be difficult.
• This is where Ultrasound Tissue Characterisation (UTC) can have a role
• There may not be value in monitoring structural changes compared with monitoring clinical severity, as pain symptoms may resolve earlier.
• UTC appears to detect pre-symptomatic Achilles tendon changes; there may be value in screening certain cohorts.
• UTC may be able to detect occult tendinopathic changes within clinically normal tendons that are not visible on ultrasound imaging.
• There is a poor correlation between pain and structural pathology.

Plantaris – Its role in the athlete – assessment and management – Mr James Calder, Consultant Orthopaedic Surgeon, Fortius Clinic, London

• Medially located Achilles tendon pain may be due to plantaris
• Plantaris tendon is present in around 98%¹
• The insertion of plantaris may be slightly varied among different individuals²
• Plantaris effect may be compressive, related to neuroinflammatory mediation or result in less capacity for elongation.
• Excising the plantaris tendon in elite athletes with non-insertional Achilles tendinopathy may have a role³
• Plantaris should be investigated as a possible cause of Achilles pain.
• Heavy slow resistance may help when plantaris is involved, and surgery may be considered if conservative treatment fails.

Neural Aspects of Achilles Tendinopathy – Dr Polly Baker, Consultant in Sport and Exercise Medicine and Honorary Research Fellow, University of Brighton

• Hypoxic tissue produces vascular endothelial growth factor (VEGF) which leads to neovascularisation and stimulates axonal outgrowth.
• There seems to be an upregulation in pain in Achilles tendinopathy
• Ongoing pain may be due to nociception or persistent inflammation, or psychological factors
• Nerve injury may also cause neovascularisation
• Neural assessment gives an understanding of the aetiology, and should be an essential part of examining patients with Achilles tendinopathy.

Is Tendinopathy and Inflammatory Condition? – Professor Andy Carr, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford

• Immune cells are players in tendon repair – inflammation is an important contributor in tendinopathy
• Perhaps clinicians should avoid using emotive terms such as “degeneration” to describe tendon changes
• Tendon cells do not turn over; the tendon we make in adolescence stays with us for life.
• Tendon cells may behave in a semi-inflammatory fashion
• Neurosensitisation may be an important factor in nociception
• Central sensitisation is implicated by both upregulation of glutamate and increased sensitisation to glutamate.
• Steroid injections switch off “good” and “bad” inflammation.
• In the future, there may be anti-inflammatory medications which may be available for tendinopathy
• Platelet-rich plasma (PRP) may be bad for tissues – apoptosis has been observed in histological tendon samples.

How do our models of tendinopathy help us treat patients? – Dr Jonathan Rees, Consultant in Rheumatology and Sports Medicine, Honorary Senior Lecturer, Addenbrooke’s Hospital

• Cook and Purdam’s continuity model^4,5 and Fu’s failed healing response model⁶ are easy to understand
• Modulation of the inflammatory response may be a potential option
• Neovascularisation is described in osteoarthritis, rheumatoid arthritis, ankylosing spondylitis, diabetic neuropathy, malignancy, ischaemia. To say that tendon degeneration alone is causing neovascularisation without an inflammatory mechanism does not make sense
• Macrophages, T and B lymphocytes are seen in chronic Achilles tendinopathy using monoclonal antibodies to CD68, CD3 and CD20 – inflammation is implicated^7,8.
• Current models may not have the complete story.

Tendinopathy: physiotherapy and rehabilitation – Dr Bruce Paton, Clinical Specialist Physiotherapist, Lower Limb Extended Scope Practitioner, University College Hospital

Optimum rehabilitation goals are to restore:

• the load function of the tendon
• adequate tendon stiffness
• adequate stretch-shortening behaviour
• load dissipation
• an effective kinetic chain
• a pain-free state.

Loading programmes:

• Concentric – some evidence that this may be effective⁹
• Eccentric – best treatment available.^10,11 Clears majority of midsubstance but not all
• Isometrics – give some short-term pain relief and cortical inhibition, and may be good for reactive/compressive tendinopathy¹²
• Heavy slow resistance – seems to be effective in patellar tendinopathy,¹³ now also evidence in Achilles tendinopathy.

Other rehabilitation considerations:

• Possibly the kinetic chain
• Neurodynamics have a role
• Address psychosocial factors such as fear avoidance
• Mixed evidence for pushing through pain
• Address metabolic factors such as obesity.

What evidence do we need to translate into practice to better manage tendinopathy – and how? – Dr Dylan Morrissey, Consultant Physiotherapist and Clinical Reader, National Institute for Health Research

• Need to consider evidence based on physical activity vs exercise vs sport – there may be differing evidence for the elite level athletes vs weekend warriors vs the sedentary.
• A case study illustrating the importance of thinking around the problem and expecting the unexpected.

Conclusion

The Orthopaedic Research UK’s Tendinopathy conference was informative and thought-provoking.   Tendinopathy is a frequently encountered clinical problem which can prove challenging to manage.  Hopefully the conference will become a regular event in the sport and exercise medicine calendar.

References

1. Saxena A, Bareither D. Magnetic resonance and cadaveric findings of the incidence of plantaris tendon.   Foot Ankle Int. 2000 Jul;21(7):570-2.
2. van Sterkenburg MN1, Kerkhoffs GM, Kleipool RP, Niek van Dijk C. The plantaris tendon and a potential role in mid-portion Achilles tendinopathy: an observational anatomical study.  J Anat. 2011 Mar;218(3):336-41.
3. James D F Calder Richard Freeman Noel Pollock.  Plantaris excision in the treatment of non-insertional Achilles tendinopathy in elite athletes.  Br J Sports Med 2015;49:1532-1534.
4. 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 Jun;43(6):409-16.
5. Cook JL, Rio E, Purdam CR, Docking SI. Revisiting the continuum model of tendon pathology: what is its merit in clinical practice and research?  Br J Sports Med. 2016 Oct;50(19):1187-91.
6. Fu SC, Rolf C, Cheuk YC, Lui PP, Chan KM. Deciphering the pathogenesis of tendinopathy: a three-stages process.  Sports Med Arthrosc Rehabil Ther Technol. 2010 Dec 13;2:30.
7. Rees JD, Stride M, Scott A. Tendons–time to revisit inflammation.  Br J Sports Med. 2014 Nov;48(21):1553-7.
8. Rees JD. The role of inflammatory cells in tendinopathy: is the picture getting any clearer?  Br J Sports Med. 2016 Feb;50(4):201-2.
9. Wetke E, Johannsen F, Langberg H. Achilles tendinopathy: A prospective study on the effect of active rehabilitation and steroid injections in a clinical setting.  Scand J Med Sci Sports. 2015 Aug;25(4):e392-9.
10. Frohm A, Saartok T, Halvorsen K, Renström P. Eccentric treatment for patellar tendinopathy: a prospective randomised short-term pilot study of two rehabilitation protocols.  Br J Sports Med. 2007 Jul;41(7):e7. Epub 2007 Feb 8.
11. Habets B, van Cingel RE. Eccentric exercise training in chronic mid-portion Achilles tendinopathy: a systematic review on different protocols.  Scand J Med Sci Sports. 2015 Feb;25(1):3-15.
12. Rio E, Kidgell D, Purdam C, Gaida J, Moseley GL, Pearce AJ, Cook J. Isometric exercise induces analgesia and reduces inhibition in patellar tendinopathy.  Br J Sports Med. 2015 Oct;49(19):1277-83.
13. Kongsgaard M1, Qvortrup K, Larsen J, Aagaard P, Doessing S, Hansen P, Kjaer M, Magnusson SP. Fibril morphology and tendon mechanical properties in patellar tendinopathy: effects of heavy slow resistance training.  Am J Sports Med. 2010 Apr;38(4):749-56.

Dr Farrah Jawad is a registrar in Sport and Exercise Medicine in London.  She has previously worked in the Tendinopathy clinic at the Institute of Sport, Exercise and Health in London and currently works at Homerton University Hospital.  She has recently completed her MSc in Performing Arts Medicine at UCL, for which she has been nominated for the Dean’s Prize.  Farrah co-ordinates the BJSM Trainee Perspective blog.