Proximal hamstring tendinopathy: An Overview of Symptoms, Causes & Treatments

WHY ARE HAMSTRING MUSCLES ARE PRONE TO INJURY?

The hamstring muscles consist of three primary muscles: the semimembranosus, semitendinosus, and biceps femoris. These muscles are situated in the posterior (back) part of the thigh, and are associated with proximal hamstring tendinopathy. 

The proximal (upper) part of these hamstring muscles attaches to the ischial tuberosity. This attachment site plays a crucial role in the function of the hamstrings. 

When the hip flexes, such as during activities like running or sprinting, the hamstring muscles are stretched. This elongation makes them more susceptible to injury, particularly in the area where they attach to the ischial tuberosity. 

Interestingly, sitting for prolonged periods can also increase the risk of hamstring injuries. The pressure exerted on the pelvis while sitting can place additional stress on the tendons that connect the hamstrings to the ischial tuberosity, further increasing the chance of injury, swelling and pain. 

PROXIMAL HAMSTRING TENDINOPATHY: HOW DOES IT HAPPEN?

Proximal hamstring tendinopathy is a condition that can develop due to a variety of factors, including individual characteristics and lifestyle choices. 

These are some of the main risk factors for developing the condition: 

1. Running: Middle or long-distance running, which involves repetitive and high-intensity use of the hamstring muscles, is a known risk factor for proximal hamstring tendinopathy.
2. Age: Individuals over the age of thirty are at a higher risk, as tendons tend to become less flexible and more susceptible to injury with age.
3. Participation in Kicking Sports: Participation in sports that require frequent kicking motions, such as soccer or AFL can increase the risk of developing proximal hamstring tendinopathy, as  these actions put additional strain on the hamstring tendons.
4. Muscle Tightness: Having tight hamstrings, glutes, and lower back muscles can contribute to the development of this condition. Muscle tightness can create imbalances and increase the load placed on the hamstring tendons during physical activities.
5. Poor Warm-up and Stretching: Inadequate warm-up routines before physical activity or insufficient stretching of the hamstring muscles can increase the risk of proximal hamstring tendinopathy. Proper warm-up and flexibility exercises help prepare the muscles and tendons for the demands of exercise reduce the risk of injury.
6. Biomechanical Factors: Individual biomechanical factors, such as gait abnormalities, muscle imbalances, and poor running or exercise techniques, can contribute to the development of this condition.

TREATING CHRONIC PROXIMAL TENDINOPATHY 

Treating chronic proximal hamstring tendinopathy can be a multifaceted process, especially if the condition has been present for an extended period. 

Many people with this condition experience symptoms for many months before seeking treatment, which makes treatment more complex.  

Here are some common treatment approaches to address this condition:

1. Rest and Activity Modification: One of the primary components of treatment is rest and the avoidance of activities that exacerbate the condition. For runners and athletes, temporarily ceasing activities that strain the hamstring tendons is typically advised to allow for healing.
2. Application of Ice and Heat: Alternating between ice and heat applications can help manage pain and inflammation associated with tendinopathy. Ice can reduce swelling and numb the area, while heat can improve blood flow and relax tight muscles.
3. Stretching and Strengthening Exercises: A physiotherapist can prescribe specific stretching and strengthening exercises tailored to the individual’s needs. These exercises aim to improve flexibility, strength, and endurance in the hamstring muscles, which can aid in the healing process and prevent future injuries.
4. Manual Therapies: Physiotherapists may also use manual therapies such as massage or dry needling to alleviate muscle tension, improve blood circulation, and promote tissue healing in the affected area.
5. Pain Relief Medications: Over-the-counter pain relief medications can be used in the short term to manage pain and discomfort.
6. Gradual Return to Activity: Once the symptoms have improved and the hamstring tendons have had time to heal, a gradual return to physical activity is recommended. This should be done under the guidance of a physiotherapist to prevent re-injury.

With adequate treatment and time, this injury will heal. A physiotherapist can further provide advice on preventing this injury in the future, and tailor a treatment plan to your needs. 

Case study

Case series discussion #1: Proximal hamstring tendinopathy.

Mrs S is a 52 year old lady who experienced gradual onset ache at the base of her buttock region, without trauma or incident at time of onset. This corresponded with a period of increased walking duration, which she performed daily as exercise. Pain intensity progressively worsened across a three-month duration, and was most intense while sitting and during the first few steps of the day after waking. Mrs S also experienced pain after walking for longer than an hour continuously, and pain remained elevated for the remained of that day and the following morning. Pain progressed until driving (sitting) was only tolerable for 20 minutes before a break was required, at which point she sought health care assistance.

Mrs S was referred by her regular GP for physiotherapy opinion and management. Objective testing revealed sharp pain localised to biceps femoris hamstring insertion on the posterior inferior iliac spine, and her pain was able to be replicated at this region with resisted hip extension active motion particularly when performed from a starting position of hip flexion (increased compression over the insertion site). Hip and lumbar active range of motion were regular, and nerve provocative testing did not reproduce any symptoms. Objective findings, combined with subjective history, led to a diagnosis of proximal hamstring tendinopathy.

Physiotherapy intervention consisted education for pain-guided load management. Specifically, a pain threshold of 3/10 on a numerical pain rating scale (where 0=no pain and 10=worst pain imaginable) was agreed upon as the limit for acceptable pain during activity before requiring modification or cessation. Additionally, the client was instructed to monitor the delayed response to activity (the morning after activity), and if symptoms were elevated the activity was to be modified to make it easier/less provocative.

The client’s pain tolerance during resistance exercises was assessed; non-compressive (hip in neutral) were targeted to minimise aggravation. The aim of this exercise was to fatigue the hip extensors and knee flexors (and resultingly build strength and activity-capacity), while minimising pain aggravation. Initially, the client was prescribed prone machine-based knee flexion and top-position isometric single leg bridging exercises (figure one), as these were within the acceptable pain-threshold, and were tiring within 10 repetitions and 20 seconds respectively. This was performed every second day.

Pain management therapy was also provided to the client, in the form of soft tissue massage to all hamstring muscles (not the tendon insertion site). The client was shown foam rolling exercise, and instructed to use this for relief as required.

Within two weeks, the single leg isometric bridge was comfortable through range (isotonic), and was progressed accordingly. The client was educated on self-progression for the prone machine-based knee flexion exercise, whereby if this activity did not aggravate symptoms (per the pain threshold and delayed pain response established) after four repeats, and fatigue wasn’t being reached, an additional weight plate (2kg) was added.

After 6 weeks, Mrs S reported she experienced no pain with sitting or in the morning. The only aggravating activity was walking for durations longer than one hour, although pain intensity was considerably lower with this activity. Mrs S was instructed to reduce walking duration to the onset of pain (approximately one hour), and to apply the same self-progression principles established for resistance exercise. She continued her resistance exercise, which she reported were pain-free and her strength greatly improved.

After a further month, Mrs S had resumed her pre-injury walking duration without any symptoms during or after.

Discussion

Proximal hamstring tendinopathy is considered an insertional tendinopathy, affecting the biceps femoris hamstring muscle insertion to the posterior inferior iliac spine. Accordingly, compression is considered the primary offending load, rather than tensile forces as is more typical of mid-portion tendinopathies. It is recommended that compression is minimised particularly in the early phases of rehabilitation in insertional tendinopathies.

As is typical of rehabilitation for other lower limb tendinopathy conditions, best current management is considered gradual and progressive resistance exercise that also incorporates plyometrics/energy store-and-release exercise, followed by sports specific training. This should be at the back-end of rehabilitation. Rehabilitation exercise can be pain-guided, limiting pain during activity to mild levels only (approximately 3-4/10), but it doesn’t necessarily have to be pain-free.