Proximal Hamstrings Tendinopathy (PHT) is an injury common to sprinters and jumping athletes that manifests as pain in the lower part of the hamstring tendon near the knee. Basically an injury to where your hamstring muscle group attaches to your ‘sit bones’ (ischial tuberosity for the anatomy geeks out there).
Research states it is “insertional tendinopathy, and compression of the tendon at its attachment during hip flexion/adduction”. In other words, it is irritation and/or tearing where the hamstring tendons commonly attach to the ischial tuberosity that is usually made worse bending your hip and bringing your thigh closer to the midline.
CAUSES
A quick list of potential causes of PHT includes increasing training volume/intensity too quickly, the sudden introduction of sprinting, lunging, hurdles, or hills. All of these activities require the hamstrings to contract or lengthen while in hip flexion and may result in provocative tensile and compressive load at the tendon insertion. It may also happen with excessive use of static stretches (far too many of my patients talk about how much they stretch their hamstrings but almost no one talks about strengthening them) in yoga and Pilate postures involving sustained end-range hip flexion. Even the compressive load from prolonged sitting can be irritating to some sufferers of severe PHT.
RISK FACTORS
Risk factors of PHT are age, body mass index, metabolic issues, hormonal changes, and some medication side effects. It is of note that perimenopausal women may be at higher risk as the loss of estrogen can negatively affect tendon resilience.
TREATMENT
The most important component to recovering from PHT is progressively strengthening the hamstring tendon. Initial exercises load the hamstring with very little hip flexion. This allows us to strengthen without further damage. Exercises such as slider hamstring curls work well for that.
Researchers have conveniently broken down a 4 stage approach to rehabilitating PHT based on the evidence they reviewed. They stress the importance of monitoring pain during the program and state that some pain is expected with the exercises but should resolve after 24 hours. The individual response of each individual patient will govern the progression of the proposed stages. For details please consult the reference, specifically figures 1-5 and work with your physiotherapist for guidance.
Stage 1 Exercises (Isometric loading)
The first phase focusses on isometric (tightening the muscle without moving the limb) in positions that do not compress the PHT in order to load the muscle/tendon and reduce pain when it is irritated as it has been shown to have a pain-reducing effect. There should be a notable reduction in pain after these exercises when load testing the hamstring afterward. The hip needs to also be in almost neutral position (possibly 20-30 degrees of flexion) to minimize compression on the PHT.
Example exercise but not limited to:
- isometric leg curl
Stage 2 Exercises (Isotonic Hamstring Load With Minimal Hip Flexion)
For stage 2, heavy slow resistance (HSR) is needed for both concentric (muscle shortening against resistance) and eccentric (muscle lengthening against resistance) as this was documented to be easier to complete by patients. This type of exercise has been shown to be comparable in results to the widely accepted isolated eccentric exercise used in most tendinopathy rehabilitation programs. It was seen that HSR showed better collagen turnover in injured tendons than submaximal eccentric contractions. The focus with HSR is on slow, fatiguing, resisted movements starting at low resistance high reps and progressing to higher resistance and lower reps done every other day. The contractions are held for 3 seconds each for a total of 6 seconds. Loaded hip flexion is avoided to minimize compression on the PHT. Single-leg movements are also important to address asymmetrical loss.
Example exercise but not limited to:
- prone leg curl
- Nordic hamstring exercise
Stage 3 Exercises (Isotonic Exercises in Positions of Increased Hip Flexion 70-90 degrees)
The goal of this stage is to continue hamstring muscle strength, hypertrophy and functional position training while progressing into more hip flexion. This phase can be started when the patient can tolerate higher loading hip flexion tests like a lunge. These can be done every second day with a slow and controlled technique being paramount. Hip flexion can progress to 70-80 degrees. At the end of stage 3, there should be little or no pain on more sport-specific movements in the affected PHT.
Example exercise but not limited to:
- walking lunges
- deadlifts
- Romanian deadlifts and the “diver”.
Stage 4 Exercises (Energy Storage Loading)
The final stage is only required for patients returning to sports involving lower-limb energy storage or impact loading. Reintroducing the power and elastic stimulus for the hamstring can begin when the hamstring loading tests produce little to no pain. Because these exercises pose the greatest load on the PHT, they are done every third day.
Example exercise but not limited to:
- kettlebell swings
- alternate-leg split squats
