Located, sharp lower back pain is the most common symptom of LS. Pain often limits the range of motion of the lumbar spine and certain movements, particularly those requiring ventral or lateral flexion, may not be executable. Many patients also claim muscle spasms. They may comprise any of the above mentioned muscles and are generally perceived directly lateral to the lumbar spine.

Acute complaints can often be related to a single event, a sports accident or an unfortunate move. In contrast, patients suffering from chronic lower back pain frequently report continuous physical stress for professional reasons or due to training.

Of note, the additional presence of generalized or radiating pain, numbness, paresthesias, blunted reflexes, loss of urethral or anal sphincter control indicate more severe lesions, e.g., lumbar disc herniation, lumbar radiculopathy or lumbar spinal stenosis [8] [9].

• Back Pain

  Lumbar strain is a painful injury of musculature, ligaments and/or tendons of the lower back. They usually result from physical overload and trauma. Located, sharp lower back pain is the most common symptom of LS. [symptoma.com]

  The majority of lower back pain is directly associated with lower back or lumbar strain which is an injury to the muscles or ligaments in the lower back region. [sportsrehabcoach.com]

  Diagnostic imaging tests such as X-rays may also be performed to rule out dangerous causes of back pain before initiating lower back strain treatment. [raleighspinesurgeon.com]

• Low Back Pain

  Definition/Description Lumbar strain is a commonly wielded diagnosis (Depalma 2011, Houglum 2001) for mechanical low back pain but is without anatomical or histologic evidence. [physio-pedia.com]

  It is extremely important to keep the back straight so it is supported by the back of the chair. One word of caution if you push yourself before your low back pain is healed then you could end up with chronic low back pain thus permanent injury. [sportsrehabcoach.com]

  There are many factors which can lead to low back pain and one of them is Lumbar Strain. What Is Lumbar Strain? In order to understand what is Lumbar Strain one needs to understand what is the low back made up of. [epainassist.com]

• Spine Pain

  Second, it is necessary to determine whether the acute or chronic spine pain is related to a serious underlying medical illness that is manifesting itself as spine pain. [clevelandclinicmeded.com]

  Referred Pain to the Lumbar Spine Pain in the area of the lumbar spine may be due to important problems that are actually unrelated to the back. Referred pain occurs when a problem in one place in the body causes pain in another place. [hss.edu]

Diagnosis of LS is based on thorough anamnesis and clinical examination.

Patients should be questioned regarding the precise event that triggered acute lower back pain, possible pain radiation and movements that exacerbate symptoms. It is also important to learn about the patient's profession and recreational activities that may be associated with increased mechanical loads of the lumbar spine. This information should be related to the patient's medical history: Did they experience LS before? How were previous episodes of this pathology triggered? If recurrent lower back pain can't be related to acute or chronic physical overload, the patient's family history may point at inheritable muscle and connective tissue disorders.

Uncomplicated cases of LS hardly require additional analyses. However, neurologic symptoms are not characteristic for LS and should prompt further diagnostic measures. This also applies if doubts about vertebral spine, intervertebral disc or spinal nerve involvement remain due to other observations. Plain radiographic images obtained in anteroposterior and laterolateral views may be of great help to evaluate the former [10]. Magnetic resonance imaging is the method of choice to confirm or rule out the latter [9].

Treatment of LS is mainly supportive. Local application of cold or heat is generally perceived to be very pleasant and bears lower risks than drug therapy. However, intense pain may require medication. In this context, non-steroidal anti-inflammatory drugs are frequently prescribed. They also reduce tissue inflammation and swelling. Additionally, patients suffering from muscle spasms may benefit from muscle relaxants. Refusal of drug intake may lead to prolonged pain, involuntary posture changes and subsequent muscle strains and spasms. While massages may be helpful, there is no scientific evidence regarding the effectivity of acupuncture.

Except for periods of intense pain, bed rest is no longer recommended to treat LS. In order to accelerate recovery and to prevent recurrent injury, patients may instead undergo physiotherapy and should aim at returning to their usual activities as soon as possible. Here, stretching and strengthening exercises should be combined with advice regarding weight lifting or realization of other tasks without submitting the lumbar spine to heave mechanical loads. Abdominal, dorsal and gluteal muscles should be trained equally. Body posture should be analyzed and possibly corrected during and after recovery from LS.

Prognosis is excellent if LS results from minor muscle lesions and neither nervous nor osseous structures are involved. Pain typically subsides within one or two weeks and athletes may return to training after one month.

In general, LS is provoked by mechanical overload of soft tissue that surrounds the lumbar spine. With regards to acute injury, such increased physical loads often result from strenuous single movements, e.g., from lifting heavy weights, or from combined motions such as forward or lateral flexion and simultaneous rotation of the lumbar spine. This applies particularly if the patient is not used to these movements because they either increased training intensity too fast or carried out tasks they usually don't realize. Traumatic injury is also very common in contact sports and may lead to more severe lesions [2] [3]. Overuse due to countless repetitions of similar movements is seen in sports like gymnastics and may trigger chronic lower back pain.

Of note, the aforementioned mechanical overload is not necessarily associated with very strenuous movements, but may also result from ordinary motions if a patient's musculature and connective tissue are less resistant than those of a healthy individual. In this context, muscular disorders affecting spinal or abdominal muscles as well as disturbances of nervous conduction and/or proprioception shall be mentioned as examples for conditions predisposing a patient to LS. Additionally, any spinal pathology forcing the affected person to adopt an abnormal posture alter the distribution of loads lumbar spine and surrounding soft tissues are submitted to and increase the risk for LS [4].

LS is a very common injury and accounts for significant shares of muscle strains and lower back lesions, respectively. However, exact numbers cannot be provided here because affected individuals don't necessarily consult their physicians.

Many patients presenting with LS either sustained that injury while doing sports or while realizing handicraft work. Some sports are associated with higher risks of LS than others, e.g. rugby, American football, gymnastics and figure skating [5]. These risk factors are directly related to the age distribution of LS and this injury is most commonly diagnosed in young and middle-aged adults who usually engage in such activities. LS may occur in pediatric patients who are submitted to intense training.

Men seem to be affected more often than women.

No racial predilection has been reported.

As per definition, LS results from an injury to muscles, ligaments and/or tendons of the lower back. Patients suffering from LS typically claim pain that is perceived in the aforementioned structures. Nociception is mediated by specialized neurons whose somata are located within the dorsal root ganglia of the corresponding spinal nerve. These neurons are activated by mechanical stimuli such as acute or chronic overload of lumbar musculature and connective tissue. Of note, chronic pain may not be related to an identifiable physical injury.

Lumbar lesions may not be restricted to these tissues and more severe injuries may provoke similar symptoms. In order to recognize and possibly predict pathophysiological events that may occur in patients suffering from LS, comprehensive understanding of position and function of anatomical structures of the lumbar region is required. The following list may serve as an orientation:

• Lumbar multifidus muscles originate from each lumbar vertebra's mamillary processus and insert at the spinous processes of superior vertebrae. These muscles allow for spinal extension (upon bilateral contraction) as well as lateral flexion and rotary motions (upon unilateral contraction) [6] [7].
• Additionally, all spinal erectors, i.e., musculi spinalis thoracis, longissimus thoracis and iliocostalis lumborum, may be affected in patients presenting with LS.
  
  
• The lumbar spine itself consists of five vertebrae which are designated L1 to L5. It forms part of the axial skeleton and is located between thoracal spine and os sacrum.
• Intervertebral joints are formed by superior and inferior articular processes of adjacent vertebrae. With regards to the lumbar spine, these joints largely facilitate ventral flexion and dorsal extension while rotary motions are limited.
• Intervertebral discs cushion spinal movements and are located between each two neighboring vertebrae [8].
• Five pairs of spinal nerves emerge from the lumbar spine. Intervertebral foramina harbor their dorsal root ganglia and any lesion occurring in this area may provoke lumbar radiculopathy.

Preventive measures can be deducted from LS etiology and comprise:

• Avoidance of heavy weight lifting
• Use of protective equipment and back protectors while realizing tasks associated with increased physical loads on the lumbar spine
• Adoption of a healthy posture
• Regular exercise to strengthen abdominal, dorsal and gluteal muscles
• Warm-up and gradual increase of training intensity, avoidance of overtraining

Lumbar strain (LS) is a very common type of injury. Physical overload or trauma result in lesions of muscles, ligaments and/or tendons of the lumbar region, i.e., of the lower back. Although this type of injury may involve damage to the lumbar spine, this is rarely the case. Spinal nerve damage, radiculopathy and lesions of lumbar vertebra are often associated with worse prognoses and generally require prolonged therapy. They are beyond the scope of this article and will only be considered as differential diagnoses.

Patients suffering from LS present with lower back pain and a decreased motion range. Sudden onset of these symptoms is characteristic and patients often report to have felt an acute "pull" while doing sports, lifting weights or realizing any other movement they are not accustomed to. These activities may result in excessive stretching and microtraumas to muscle fibers. Less frequently, LS is caused by more severe muscle injuries.

The aforementioned etiologic factors may account for the fact that LS are mainly diagnosed in young and middle-aged adults. However, this condition may affect patients pertaining to any age group. Diagnosis is generally based on anamnesis and physical examination. Diagnostic imaging is only required if more severe injuries cannot be ruled out.

Treatment initially consists in rest, local application of heat as well as systemic administration of analgesics and possibly muscle relaxants. Distinct measures may be taken to avoid repeated injury: If physical overload resulted from overtraining, patients should be advised to increase exercise intensity gradually. Thus, exercise intensity should be reduced. In contrast, normal loads may cause LS in patients whose daily routine does include very little exercise. Muscles, ligaments and tendons supporting their spine are rather weak. These patients may benefit from physiotherapy and regular exercise. Back protectors should be worn by those people who can't or won't avoid high lumbar loads due to professional reasons or recreational activities.

Most LS cases resolve within two weeks. If symptoms persist for more than three months, the condition is designated chronic lower back pain [1].

Lumbar strain (LS) describes an injury to muscles, ligaments and/or tendons of the lower back. It is a very common lesion resulting from mechanical overload of the lumbar spine and surrounding soft tissues.

Causes

In general, the aforementioned overload may be provoked by two distinct scenarios: Either lumbar spine and strengthening musculature are submitted to intense physical strains or weakened tissues are injured while submitted to normal loads.

Most LS are triggered by the former. An unfortunate move while realizing handicraft, a traumatic sports accident or continuous overuse due to profession or recreational activities may cause acute or chronic lower back pain, respectively.

Weakness of abdominal, dorsal and gluteal muscles, muscle or connective tissue disorders may predispose patients for LS.

Symptoms

Characteristic symptoms are lower back pain and possibly muscle spasms in close proximity to the lumbar spine. The lumbar spine's motion range is generally reduced, i.e., certain movements cannot be carried out.

An uncomplicated LS does neither involve nervous nor osseous tissue injury. Thus, numbness, tingling sensations, radiating pain and problems with micturition or defecation are not to be expected in LS patients. Such symptoms rather point at lesions of the lumbar spine itself or nerves emerging from here.

Diagnosis

Diagnosis of LS is based on the patient's medical history and clinical examination. Additional diagnostic measures are rarely indicated but should be carried out if neurological symptoms are observed or if the patient's condition does not improve within short periods of time. In these cases, plain radiography or magnetic resonance imaging may be required.

Treatment

Conservative treatment is generally sufficient. Local application of cold or heat may help to reduce inflammation and pain. Analgesics and possibly muscle relaxants may be prescribed to relieve pain and muscle spasms. Refusal of drug intake may cause patients to adopt poor postures, which may, in turn, cause additional muscle strains and spasms.

Physiotherapy, stretching exercises and gradual return to day-to-day activities are preferred over prolonged bed rest. The latter is only indicated in periods of acute pain.

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