Anatomy
The hamstring muscle group consists of three main muscles: biceps femoris, semimembranosus and semitendinosus. Biceps femoris has two heads with the short head originating from the linea aspera and thus only acting on the knee joint.
Biceps femoris has a dual innervations, with the long head being innervated by the tibial portion of the sciatic nerve (L5, SI -3), whereas the short head is innervated by the common peroneal division (L5, S1 -2).
The posterior portion of the adductor magnus is sometimes considered functionally as a hamstring due to its anatomical alignment. Adductor magnus is involved in hip extension and adduction and has innervations from the tibial portion of the sciatic nerve, like the majority of the hamstring group.
Clinical Perspective
The effective management of posterior thigh pain is dependent upon correct diagnosis . Initially, the practitioner must determine whether the injury to the posterior thigh is a muscle strain or pain referred from elsewhere. This is not always a simple process. However, if not established, the athlete, practitioner and coach may be frustrated by a recurrent injury that hinders a successful return to sport.
In healthy individuals, a strain to a large muscle group such as the hamstrings is the result of a substantial force. The athlete should recall a particular point in time that the incident occurred and whether a significant force was applied to the muscle. Practitioners should be reticent to diagnose a muscle strain in the absence of these findings. Often this fundamental but common mistake will lead to inappropriate treatment. Tethering of neural structures or fascia! strains in the posterior thigh can also occur as an incident, however, appropriate examination will reveal whether the injury has a fascial or neural component. The challenge in patients with posterior thigh pain is to distinguish between a muscle strain and referred pain from the lumbar spine or gluteal muscle trigger points.
History
Posterior thigh pain that is not the result of a hamstring strain will require skilful clinical reasoning to determine the cause. This involves not only an intricate knowledge of the local anatomy and possible abnormalities but also an understanding of the structures that can refer pain into this region. Practitioners should be aware of the wide variety of assessment and treatment techniques used around the pelvis in order to make an accurate diagnosis. Systems of treatment often are associated with a specific diagnosis. Therefore, a common fault in manual medicine is to make the diagnosis based on what best fits with the treatment technique of choice.
The inability to utilize alternative techniques leads a practitioner to the inevitable conclusion that the presenting injury can only be a result of a diagnosis that fits in with the technique they are most competent in using. For example, a practitioner unskilled in sacroiliac management is unlikely to ever diagnose referred pain from the SIJ as a cause of hamstring pain.
History taking has the same goals and objectives as any other area in sports medicine. However, because there are so many causes of posterior thigh pain, the clinician, having taken the history, must be able to formulate a definite set of goals for the subsequent examination. Otherwise, time will limit the examination or there will be confusion with the vast amount of information collected.
Examination
All examinations should commence with observation and palpation. The remainder of the examination will depend on information gathered in the history. It is beneficial to have several quick tests to screen for various factors that commonly cause hamstring pain. However, once the most likely cause of pain has been identified, the most appropriate technique of assessment should be implemented to identify the exact nature of the problem. The initial examination should be thorough but not excessive. Contributing factors or alternative sources of pain in the hamstring group can be evaluated in subsequent examinations.
1.Observation
- standing
- walking
- lying prone
2. Active movements
- lumbar movements
- hip extension
- knee flexion
- knee extension
3. Passive movements
- hamstring muscle stretch
4. Resisted movements
- knee flexion
- hip extension
- eccentric hamstring contraction
5. Functional tests
- kicking
- running
- sprint starts
6. Palpation
- hamstring muscles
- ischial tuberosity
- gluteal muscles
7. Special tests
- neural tension: slump test
- lumbar spine examination
- sacroiliac joint
- assessment of lumbopelvic stability
- biomechanical analysis
Investigations
Investigations of posterior thigh pain may be useful in defining the source of pain but practitioners must not take these findings in isolation from the rest of the examination. Both ultrasound and MRI can be used to confirm the presence of a muscle tear in cases where the diagnosis is in doubt clinically.
Referred Pain to Posterior Thigh
The possibility of referred pain should always be considered in the athlete presenting with posterior thigh pain. Hamstring pain may be referred from the lumbar spine, the SIJ or from soft tissues, for example, the proximal fibers of the glutens maximus and especially gluteus medius and the piriformis muscle .Often, there is a history of previous or current low back pain.
The slump test should be used to detect neural tightness. The test is positive when the patients hamstring pain is reproduced and subsequently relieved with reduction of the neural tension by neck extension. Examination may reveal reduced range of movement of the lumbar spine, tenderness and/or stiffness of lumbar intervertebral joint(s) or tenderness over the area of the SIJ.
A positive slump test is strongly suggestive of a referred component to the patient’s pain. However, a negative slump test does not exclude the possibility of referred pain and the lumbar spine should be carefully examined to detect any intervertebral segment hypomobility. Systematic soft tissue palpation of the hip extensors, abductors and rotators should also be performed.
Trigger Points
Trigger points are common sources of referred pain to both the buttock and posterior thigh. The most common trigger points that refer pain to the mid hamstring are in the glutens minimus, gluteus medius and piriformis muscles. The clinical syndrome associated with posterior thigh pain without evidence of hamstring muscle injury on MRI and reproduction of the patient's pain on palpation of gluteal trigger points is now well recognized and extremely common.
The clinical features are described in. The patient will often complain of a feeling of tightness, cramping, twinge or a feeling that the hamstring is about to tear On examination there may be some localized tenderness in the hamstring although it is usually not focal and there is restriction in hamstring and gluteal stretch. Firm palpation of the gluteal muscles will detect tight bands that contain active trigger points, which when firmly palpated are extremely tender, refer pain into the hamstring and elicit a twitch response.
Treatment involves deactivating the trigger point either with ischemic pressure using the elbow local treatment the tight muscle groups, the gluteals and hamstrings should be stretched.
Lumbar Spine
The lumbar spine is a source of pain referral to the posterior thigh. Unfortunately, it is difficult to distinguish between sources based on the behavior and distribution of the pain. Pain may be referred from the disk, zygoapophyseal joints, muscles, ligaments or any structure that can produce pain locally in the lumbar spine.
Nerve root compression may also be a cause of hamstring pain. Diagnostic blocks and provocation injections have been advocated to isolate sources of pain in the lumbar spine. However, in the clinical setting, this is often not possible. It is important to examine the lumbar spine carefully. This will assist in the identification of the lumbar spine as a source of hamstring pain. It is also important to remember that the lumbar spine may be a cause of lumbar pain indirectly. For example, the lumbar spine may cause a biomechanical block to extension of the lower limb, resulting in overload of the SIJ and referred pain to the hamstring group.
The slump technique has been advocated as a method of treatment of hamstring pain in AFL footballers. This is a quick test and it can be carried out rapidly to assess the relevance of neural structures as a cause of hamstring strain.
True nerve root compression is usually more definitive in its presentation. The patient may have associated neurological symptoms, such as numbness and loss of foot eversion. The management of these injuries usually involves an extended period of rest and, in certain cases, an epidural injection. In extreme cases, surgical decompression of the nerve root may be warranted.
Spondylolisthesis and spondylolysis have both been implicated as a source of hamstring pain and tightness. Examination findings of positive lumbar quadrant tests or single leg standing lumbar extension are suggestive of either condition and can be confirmed with isotopic bone scan and CT. Stabilization programs are the treatment of choice as it has been shown that the deep abdominal muscles are deficient in people with back pain as a result of spondylolisthesis and spondylysis. In severe cases, corticosteroid injection under X-ray control into the deficient pars interarticularis may be effective in reducing pain from spondylolysis.
Hamstring pain occurring in the, sporting environment can often be due to loading of the lumbar spine outside of the training and competition environment. Pain in the hamstring may be the result of referred pain from the lumbar spine as a result of prolonged sitting or bending forward. Athletes in sedentary occupations should be aware that sitting posture is a cause of injury to the hamstring. Travel involving prolonged sitting prior to training and competition may cause injury. This includes car, bus or airplane travel, and care should be undertaken to limit prolonged sitting and to provide adequate lumbar support.
Lumbar referred hamstring pain may also be the result of repeated forward bending or squatting. This occurs in many manual occupations or in those with young children. Again, correct posture and lifting should be taught, along with strategies for limiting the frequency and load of bending.
Less Common Causes:
Upper Hamstring Tendinopathy
Tendinopathy of the hamstring may occur at the origin or the insertion of the hamstring muscle group. Both present with the typical inflammatory pattern of warming up with activity and an increase in pain post activity. Tenderness is easily elicited over the tendon with associated thickening.
Proximal hamstring tendinopathy is often associated with repetitive sprinting and instability of pelvic mechanics. There may be some difficulty differentiating it from ischial bursitis, which tends to be more a result of friction with sitting on hard surfaces or hamstring syndrome which has more neurological symptoms. Upper hamstring tendinopathy may respond to transverse frictions in the short term and this will often allow an athlete to continue performing. However, the prognosis is usually protracted. A hamstring strengthening program should be commenced. This condition is often resistant to treatment. We have had some success with extracorporeal shock wave treatment.
Lower Hamstring Tendinopathy
Lower hamstring tendinopathy is often the result of large volumes of resisted flexion knee exercises. It also occurs in sprinters. The pain pattern is inflammatory and the pain is localized to the tendons of the hamstring group. Posterior capsular pain should be differentiated from tendinopathy. Pain associated with knee hyperextension, such as in kicking, is usually capsular. Management consists of anti-inflammatory agents, taping to reduce load and appropriate rehabilitation focusing on biomechanical defects.
Adductor Magnus Strains
Adductor magnus strains are rare but, when they do occur, behave similarly to a hamstring strain. The mechanism tends to be more of a rotatory action of eccentric internal rotation on one hip. Prognosis tends to be far better than hamstring strains; therefore, it is important to differentiate it from strains in the hamstring. The key to differentiating this condition is careful palpation to elicit the precise location of the tissue damage. Side-lying on the affected leg allows that hamstring group to fall laterally so that ready access can be made to the adductor magnus.
Compartment Syndrome of the Posterior Thigh
While not as common as lower leg compartment syndromes, a compartment syndrome of the posterior thigh is occasionally seen. Patients present with dull pain, stiffness, cramps and weakness of the posterior thigh during and after training. Two groups of patients with this syndrome are seen: endurance athletes without a history of trauma, and those with a history of hamstring injury. Conservative management has not been successful and posterior fasciotomy of the thigh appears to be an effective treatment.
Vascular
Endofibrosis of the external iliac artery usually produces pain in the lateral and anterior thigh. However, in some cases, pain may be experienced in the posterior thigh. This condition is associated with cycling and has been observed in triathletes. The pain is claudicant in nature. Pain may arise after 15-20 minutes of exercise but usually ceases immediately with the cessation of exercise.
On examination, a bruit is heard during the exercise that causes the pain. Diagnosis may be confirmed with echography or arteriography. If the condition is affecting performance, then treatment is either surgical or balloon dilation of the area where the artery is narrowed.
Treatment
- Physical therapy may be necessary for some people. You may feel pain at the site of the incision
. - The original pain may not be completely relieved immediately after surgery
. - Aim to keep a positive attitude and diligently perform your physical therapy exercises if prescribed
. - Schedule a follow-up appointment with your surgeon after surgery
. - The recovery time varies from depending on the underlying disease treated and your general health
. - Good posture during sitting, standing, moving, and sleeping.
- An ergonomic work area.
- A positive attitude and relaxation techniques.
- Appropriate exercise program.
