The term ‘back problems’ here includes back pain, disability, injury, and deformity.
Alexander only makes passing reference to back problems, mainly because Alexander emphasizes the educational aspect of the Technique, but probably also because historically low back pain only became a prominent problem after World War II. Since the 1990s most introductory books to the Alexander Technique would mention the Technique as a beneficial component for people with back problems.
The ATEAM study published in 2008 in the British Medical Journal was an important milestone in providing scientific evidence for the effectiveness of the Alexander Technique for the specific problem of low back pain.
There are only two references in Alexander’s writings to people with back problems, but mainly for the purpose of criticizing remedial exercises: 1. a young girl with spinal curvature in the early days of teaching in Sydney, and 2. a pupil who had been treated by ‘a well known specialist in Boston’.
Dr Wilfred Barlow points out the shortcomings of traditional approaches to back problems in a 1947 article, ‘Anxiety and Muscle Tension’. He also discusses some case histories which include people with back pain in several of his papers.   In his 1973 The Alexander Principle he cites statistics on back pain: ‘Over half the adult population experience severe lower back and sciatic pain’  – and similar statistics would become commonplace in later books on the Alexander Technique.
Eric de Peyer wrote specifically on the Alexander Technique for back problems (c. 1963):
‘If, as often happens, people have aches and pains which have defeated ordinary medical procedures it may be because a habit of muscular tension and misuse has been formed which needs to be unlearned. A great deal of chronic backache is of this kind.’
Today much introductory material to the Alexander Technique contains references to the potential benefits of the Technique to back pain and back ache.
The ATEAM study, published in the British Medical Journal in 2008, followed 579 patients over the course of a year. The study found that Alexander Technique lessons provided benefit to patients in terms of back pain relief and reducing recurrent back pain.
‘Hope for chronic back pain sufferers – The MRC ATEAM trial’ by Paul Little provides an overview of the origins, the methods, the recruitment, and other details of the setting up and running of a large trial, as well as a summary of the results.
Free Yourself from Back Pain by Noel Kingsley is an introduction to the Alexander Technique with an emphasis on dealing with back pain. The ATEAM study also led to other books specifically using the Alexander Technique for back pain. 
Back Pain Solutions by Bruce I. Kodish contains a variety of ways of dealing with back pain and the Alexander Technique is allocated 10 pages.
Change Your Posture, Change Your Life by Richard Brennan; on how the Alexander Technique can combat back pain, tension and stress.
The Posture Workbook by Carolyn Nicholls; on freeing yourself from back, neck and shoulder pain with the Alexander Technique.
It’s Your Fault by Wendy Coblentz is an autobiography of an eight year search for a cure for severe pain back, going through various medical procedures and alternative health therapies, and ending up with the Alexander Technique.
Back in Balance by Richard Brennan; on using the Alexander Technique to combat neck, shoulder and back pain.
My Back’s Knackered! What can I do about it? by Dai Richards contains advice on dealing with back pain – managing, controlling and preventing the pain in everyday life – based on ideas from the Alexander Technique.
‘Teaching to back pain’ by Kitty Breen is on teaching people with back pain, on her ‘The Educated Back™’ programme, including a list of ideas and techniques she has found useful, and further observations.
See also Pain, Research Into Benefits.