A 25 year old male, semi-elite Australian Rules footballer felt a 'twinge' in his right hamstring during a game. He presented to us the day after, complaining of tightness in his medial right hamstring and a stiff low back. He had no previous history of hamstring injury but had suffered episodic low back pain over a 5-year period.
On physical examination, the right pelvis was low compared to the left in standing position; there were tight right (45  SLR) and left (55  SLR) hamstrings and tight left hip flexors (+10  modified Thomas position). There was palpable hypertonicity through the right hamstring, left psoas, lumbar and gluteal muscles, thoracolumbar spine and right sacro-iliac joint (SIJ) motion restriction, positive Gillett's (standing S-I joint motion palpation) and extension leg raise testing for the right SIJ and weakness of the right hamstring and gluteus maximus muscles rated 4/5. Hamstring tenderness could not be localized on palpation but mild discomfort was reproduced in resisted muscle testing. Other physical examination findings and testing procedures, including Trendelenburg, valsalva, neurological, slump, lumbar ROM and hip joint motion palpation and orthopedic testing were unremarkable. The patient was diagnosed with a back-related hamstring injury on the basis of his apparent right SIJ motion restriction and pain referral. Differential diagnoses included pain referral from lumbar-pelvic myofascial structures, gluteal trigger points or a grade 1 hamstring injury with concurrent lumbar-pelvic dysfunction.
Treatment involved high velocity low amplitude (HVLA) SMT to the right SIJ and thoracolumbar spine, long axis manipulation to the right hip joint, ART to the right hamstring, left psoas, lumbar and gluteal muscles, PNF stretching of the right hamstring and left psoas and hamstring cryotherapy. Post treatment, modified Thomas position was 0  on the left, SLR 55  on the right and 65  on the left. Muscle strength was graded 5/5.
The patient did not participate in training during the week and received 2 more treatment sessions. He played a match the next weekend without re-injury. He was seen twice the next week and put on a maintenance program for the 16 weeks remaining in the season (one visit per week for a month, one visit per fortnight for a month, one visit per month thereafter). This included the above treatment plus strengthening and muscle activation work (to improve hip extension motor patterns and running technique) to the gluteus maximus, multifidus, transversus abdominus and internal oblique muscles and home advice including flexibility and stability work. MMI was reached after 10 treatments. No re-injury occurred during this period and muscle length changes continued to improve (bilateral modified Thomas position 0 , SLR 75 ).