Dr McGrath arrived in Dunedin in 1991 from the UK, and founded Dunedin Osteopathic Clinic. After twenty years of practice in central Dunedin, Christopher moved out to East Taieri to continue a smaller office practice. Outreach clinics held at Gore Hospital and then at West Otago Health (Tapanui) continued. Finally, after 30 years in Otago and Southland, Christopher moved with his wife Aeja, to Ashburton, Canterbury. He relinquished osteopathic practice to focus on consulting in musculoskeletal healthcare.

Overseas Fellow of the Royal Society of Medicine (England), member of the New Zealand Pain Society, and the Australian and New Zealand Association of Clinical Anatomists, Christopher is well published in research and professional journals. Publications and related activities and he may be found on ResearchGate.

Christopher's published scientific and editorial articles have been cited around the World, from Spain to Japan, Canada to Eastern Europe, from the UK to Scandinavia, in a wide range of journals and book chapters: medical, rheumatological, surgical, neurosurgical, anaesthetic, physical therapy, orthopaedic surgery, forensic and humanitarian nursing, medical science, osteopathic medicine, neuroscience, and medical science.

As of December 2022, his research items attracted over 13,833 reads on the academic platform ResearchGate with 249 identified citations and a 'Research Interest Score' higher than 74% of ResearchGate members, 79% Allied Health Science researchers, 76% Anatomy researchers, 67% researchers in Human Biology and 80% researchers in Physiotherapy, and h score 8.

He was active in part-time university lecturing at the University of Otago for 15 years, receiving an Excellence in Teaching award from the School of Physiotherapy in 2020 for his contribution to the teaching of clinical and functional anatomy into the postgraduate physiotherapy programme. He formerly held an Honorary Visiting Fellowship in Osteopathic Medicine at Victoria University, Melbourne.

He currently acts as a Sentinel Reader for the Health Information Research Unit, Clinical Relevance Online Rating System of McMaster University in Canada, an established global centre of evidence-based medicine. He was a long standing member of the editorial advisory board for the International Journal of Osteopathic Medicine (Int J Osteopath Med) and has been editorially involved with the Australasian Medical Journal, The Journal of Health Design, and The International Journal of Complementary and Alternative Medicine.

A long serving member of the ACC Expert Panel that developed the New Zealand Acute Low Back Pain Management Guidelines, Christopher brings a deep understanding of best practice in acute back pain. With greater than 30 years of clinical practice in NZ, UK and Australia, blended with research experience in anatomy, biomechanics and an all important focus on evidence-based practice, he uniquely holds doctoral (PhD) and master (MSc) degrees (Anatomy) from the Otago University School of Medical Sciences in addition to postgraduate diplomas in Occupational Health Practice (Otago) and in Biomechanics (Bioengineering Unit, Strathclyde University, Glasgow), having initially grained his undergraduate training as an osteopath at the British College of Osteopathic Medicine in London.

Christopher has been a glider pilot and a PPL fixed-wing pilot of 25 years with multiple ratings and aircraft types, including aerobatics. He is a keen sportsman and has experienced more injuries and surgeries than one can shake a stick at. He is also a keen pianist and focused skeet shooter.