Case Study 2: Proximal Hamstring Tendinopathy in the Female Triathlete
High level female ironman athlete returning to running following proximal hamstring tendinopathy.
Name: Age: 29 / Height: 1.70m / Weight: 60kg / BMI: 20kg/m2
Elite level female ironman triathlon athlete. Presenting for physiotherapy with a diagnosis of right proximal hamstring tendinopathy. Symptoms onset during last season but managed through. Now gradual worsening over the last month concomitant with spike in loads leading into coming up season. Currently unable to cope with normal running training load. Cycling training has also been tapered / adjusted whilst swimming loads and strength sessions increased.
Hills, speed work, long / hard bike sessions. At times sitting.
- passive pain provocation test: Modified Bent Knee Stretch Test (1).
- active pain provocation test (2):
- 3 repetitions unloaded Short Lever Single Leg Bridge, 3/10 pain score in the patient reported numerical scale (PRNS)
- 5 repetitions unloaded Long Lever Single Leg Bridge, 7/10 PRNS
- unable to execute 1 full range Arabesque unloaded.
- Running and cycling full load
- Running particularly very symptomatic if done off the bike.
- Ironman triathlon competition.
Current weekly training load
- 30km swimming across 6 sessions
- 160km bike ride over 3 sessions
- 15km running over 3 sessions and;
- 3 to 4 strength sessions per week
Clinical rationale for exercise prescription / activity modification
According to Magnusson, Langberg (3); previous paradigm where tendons were considered inert structures has been challenged by current evidence and tendons are now know to be metabolic active when mechanically loaded. Mechanically loading a tendon can lead to protein synthesis and collagen degradation. Over 24 hours’ window, in case no sufficient rest is given after exercise, collagen degradation may occur decreasing tendon stiffness and ability to manage loads efficiently. Hence, overloading can accelerate tendon pathogenesis.
However, with appropriate rest, tendons will experience a positive net collagen synthesis (Table 1). In turn, tendon loading in the presence of tendinopathy will assist in tendon regeneration, which supports an active management of this condition. Also, other proteoglycans present in the tendon matrix and enzymes that participate in molecular crosslinking can be upregulated via mechanical loading (3).
Table 1 – Collagen degradation and synthesis over time. Extracted from Magnusson, Langberg (3)
Still according to the same authors, exercise plays a significant role in the tissue concentration and release of growth factors, cytokines and prostaglandins. All of which have been linked to increased collagen synthesis and fibroblastic activity in tendons, regardless of muscular contraction type.
A particular implication for this athlete regarding the mechanical loading adaptations timeframes is that young women, using contraceptive pills, will tend to have not only a lessened basal levels of collagen but also a lower response to collagen synthesis with exercise than their counterpart males (4). Therefore, tendon adaptations are likely to be slower.
Cook and Docking (5) shed light around the concept of tissue capacity and the importance to load the entire kinetic chain. The main point is to build up capacity in all tissues surrounding the tendon instead of focusing on the tendon alone. Gradual overload is recommended according to a progression which will increase tissue demands to the targeted area, the proximal hamstring tendon this context, but also to its surrounding links. Contrary to what has been said so far in this text, these authors believe that the mechanisms by which tendon increases capacity remains unclear. Such rationale is presented on the basis that pathology may co-exists despite increased load capacity.
Tendinopathy and Pain
Considering that the levels of inflammatory markers in tendinopathy are not elevated, inflammation does not seem to be a factor in the pathogenesis of tendon pain. On the other hand, angiogenic activity, nerve ingrowth and the presence of substance P have been implicated in the painful response (3).
A complex relationship among tendon pain, motor control and muscle activity exists. The literature debates the topic to this day. The most widely accepted model is that pain alters motor control. Nonetheless, motor control changes can also precede tendon pain, leading to tendon pathology and triggering a vicious cycle (6).
Rio, Kidgell (6) also point out that people can make gain in pain reduction and functionality regardless of the presence of tendon pathology on imaging scans. The proposed mechanism would be a compensatory build-up of healthy tissue around the lesion as an adaptive response. Yet, painful tendons can exist without evidence of tissue pathology, supporting the non-linear relationship between structure and pain, where the latter cannot be considered direct result of local structural damage.
The authors above argue that apart from mechanical benefits to tendon matrix, muscle activation can induce analgesia. Nevertheless, immediate tendon pain relief seems to be better achieved by adopting isometric contractions with the assistance of external pacing devices. At 4 weeks, however, comparing the effects from an isometric protocol to an isotonic protocol of heavy slow resistance (HSR) training had no difference. Worth mentioning that sample size of this study was quite small and its results should not be extrapolated.
In part 2, I will share the protocol that was used in the treatment of this athlete and its rationale. Also, a practical example of how to monitor loads during training to avoid overloading the tendon, which would lead to unsuccessful rehabilitation commonly experienced by many clients.
Take home message
The main take home message of this section is less is more and gradual load progression is main objective of tendon rehabilitation.
- Cacchio A, Borra F, Severini G, Foglia A, Musarra F, Taddio N, et al. Reliability and validity of three pain provocation tests used for the diagnosis of chronic proximal hamstring tendinopathy. British journal of sports medicine. 2012;46(12):883-7.
- Goom TS, Malliaras P, Reiman MP, Purdam CR. Proximal Hamstring Tendinopathy: Clinical Aspects of Assessment and Management. The Journal of orthopaedic and sports physical therapy. 2016;46(6):483-93.
- Magnusson SP, Langberg H, Kjaer M. The pathogenesis of tendinopathy: balancing the response to loading. Nature reviews Rheumatology. 2010;6(5):262-8.
- Westh E, Kongsgaard M, Bojsen-Moller J, Aagaard P, Hansen M, Kjaer M, et al. Effect of habitual exercise on the structural and mechanical properties of human tendon, in vivo, in men and women. Scandinavian journal of medicine & science in sports. 2008;18(1):23-30.
- Cook JL, Docking SI. “Rehabilitation will increase the ‘capacity’ of your …insert musculoskeletal tissue here….” Defining ’tissue capacity’: a core concept for clinicians. British journal of sports medicine. 2015;49(23):1484-5.
- Rio E, Kidgell D, Moseley GL, Gaida J, Docking S, Purdam C, et al. Tendon neuroplastic training: changing
Bruno Rebello (APAM)
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