Service

The entire spectrum of spinal surgery is well developed within this division, which serves as a specialist centre for Hong Kong Island, and a tertiary/quaternary referral centre for the whole of Hong Kong and the region. Even before the formation of the division in 2000, the department was well known for its research and innovation in spinal surgery. Experience has accumulated over the past 50 years, with success reflected by numerous publications in the most reputable international journals and the continued desire of many doctors from abroad to undertake spine fellowships with us.

Over the years, the scope of spine pathology has advanced significantly, and our innovations have kept pace with this change. Accordingly, in the 60s the “Hong Kong Operation” for spinal tuberculosis was developed, in the early 70s the halo-pelvic apparatus, in the early 80s use of a titanium mesh block (one of the earliest form of cages) for anterior spinal fusion, in the late 80s transpedicular decancellation osteotomy for ankylosing spondylitis, in the 90s the fulcrum bending radiograph for scoliosis assessment, and in the new millennium intervertebral disc transplantation, plus the discovery of gene mutations in scoliosis and degenerative disc diseases.

Our services are provided in two hospitals, Queen Mary Hospital and the Duchess of Kent Children's Hospital, each taking on a special role. The Duchess of Kent Children's Hospital is internationally recognized for its care of patients with spinal deformities; including in the past, tuberculous kyphosis and post-polio deformities, and in the present day, the care of patients with scoliosis and ankylosing spondylitis. Pioneering work on the “Hong Kong Operation” for tuberculosis (anterior debridement and spinal fusion) and halo-pelvic traction for correction of deformities was carried out in this hospital, which has attracted many spine surgeons from around the world on visits. The hospital has subsequently expanded to look after adult patients with degenerative spinal conditions and the Centre for Spinal Disorders was established in 1993. In collaboration with Division of Rehabilitation, this centre provides a comprehensive service for the assessment, treatment and rehabilitation of patients through a multidisciplinary team approach including the orthopaedic surgeon, bioengineer, clinical psychologist, nurse, occupational therapist, pain specialist, physiotherapist, prosthetist, interventional radiologist and social worker. Programmes provided include the treatment of patients with chronic low back pain and failed back surgery.

As one of only two Hospital Authority-designated centres for scoliosis surgery in Hong Kong, the division has led this field by being the first to introduce: scoliosis screening in Hong Kong (in collaboration with the Department of Health). Since its introduction in 1995, we have screened over 100,000 students per year, with more than 300 students per year detected to have scoliosis and referred for early treatment. A psychosocial support programme is also introduced to help improve brace compliance; preoperative autologous blood donation programme to reduce the risk and requirement for blood bank blood; and intraoperative spinal cord monitoring using combined motor evoked potentials and corticosomatosensory evoked potentials.

Being a Level one trauma centre and the University teaching hospital, Queen Mary Hospital manages the majority of the patients with acute conditions such as spinal fractures, infections and tumours. The division has its own spinal injuries unit for the management of acute spinal cord injuries, and a Centre for Paraplegic Walking, aimed at helping those with chronic injuries to maintain mobility (see section on rehabilitation).

The division has three outpatient clinics (scoliosis, post-op follow-up and general spine) and three full day operating lists (Monday, Tuesday and Thursday) a week.

Education has always been an important part of our mission. Spine fellowships are provided in the Duchess of Kent Children’s Hospital and Queen Mary. More than 100 overseas spine surgeons have been trained in our division and many hospitol of them have taken important teaching, research and service positions all over the world. We also hold educational courses for local and regional participants. Since 2002 the division has been an International Spine Reference Centre with AO Spine, hosting two additional international spine workshops a year, as well as providing additional spine fellowships and involvement in the research and development programmes of AO Spine. Within the region, the division is actively involved in Asia-Pacific Orthopaedic Association and has formal agreements with 2 hospitals in China, Peking Union Medical Hospital in Beijing and Sun Yat Sen University in Guangzhou with the formation of collaborative spine centres for education and research.

Research

The division has an intensive programme in both basic and clinical research. Research directions for basic research are molecular biology, molecular genetics, stem cell therapy, biomaterials and biomechanics. Clinical research includes both long term prospective studies and retrospective analyses. Many of the projects are supported by competitive research funding or by with venture capital companies (see table).

The division has developed close collaborations with our own University’s Faculty of Engineering, Department of Biochemistry, and with the Department of Materials Science at City University of Hong Kong. The division has also collaborated with a number of regional and international centres of excellence including ones from Canada, Finland, Japan, Netherlands, Switzerland and USA. Notable successes have included the filing of ten patents, publications in reputable international journals (e.g. Lancet, Spine, JBJS-A, and American Journal of Human Genetics) and the attraction of industry involvement in development. For example, our work on allogeneic intervertebral disc transplantation, bioactive bone cement and super-elastic memory alloy have attracted venture capital involvement, and are at various stages of clinical trials. In particular, our pioneering work on allogeneic intervertebral disc transplantation, has demonstrated that disc transplantation is possible in human patients, with good long term results. This “world’s first” study was published in Lancet, and received widespread international coverage and acclaim.

Apart from the clinicians, we have two research assistant professors, one postdoctorate research fellow and over 20 postgraduate research students and research assistants working within the division. Our main areas of research includes genetics and molecular mechanisms of intervertebral disc degeneration, intervertebral disc regeneration and tissue engineering, intervertebral disc transplantation, bioactive bone cement, superelastic spinal implants, and surface
modification of implants.

Strategic Research Theme on Biomedical Engineering

A Strategic Research Theme (“SRT’) on Biomedical Engineering (“BME“) was formed as one of 21 strategic research themes in HKU in 2005 with the short-term goals to:

• Establish an intra-institutional Biomedical Engineering research area with three sub-themes:
  • Biomechanics, Biomaterials and Tissue Engineering
  • Biomedical Electronics, Signal Processing and Electro-physiology
  • Medical Imaging and MRI
• Foster interdisciplinary biomedical engineering research by setting up a BME research core facility platform and to encourage and foster applications for external research grants;
• Establish joint appointments or Adjunct Professorship between Faculties of Dentistry, Engineering, Medicine,
  and Science;
• Recruit research staff in the areas of biomedical engineering and related fields;
• Plan an unique integration between academia, clinical medicine and industry which enable biotechnology
  transfer.

The Faculties of Medicine and Engineering have each committed HK$25 million towards this project which is also matched by the University. Professor Keith Luk was appointed by the University Research Council as the Convener of the BME group to spearhead the theme because of the strong track record of related researches conducted in the Department of Orthopaedics and Traumatology in the past half a decade, in particular the Division of Spine Surgery. The Department is at present the most heavily involved department in this theme with no less than 20 teaching and research staff and students actively participating in research projects. To date we have jointly secured local and international competitive research grants and industrial sponsorships of over HK$30.6 million. A few large ITF (government sponsored) projects were also being approved in the past two years. More than 60 original articles, 25 abstracts/proceedings have been published and 7 international patents filed.

Recent and Ongoing Research Projects

Basic research

1. Molecular biology and Genetics
   • Genetic basis of scoliosis and intervertebral disc degeneration
   • Chemical genetics
   • Molecular mechanisms of intervertebral disc degeneration
   • Transgenic mouse models of skeletal disorders
   • Tissue engineered intervertebral disc
   • Bioreactor development
   • Stem cell therapy
   • Intervertebral disc allograft cryopreservation and regeneration
2. Biomechanics
   • Lumbosacral fixation
   • New spinal implants design and testing
   • Computer modeling of the spine
3. Material Science
   • Nitinol super-elastic implant
   • Bioactive bone cement
   • Implant surface modification (bioactive, antibacterial)
4. 4.Neurophysiology
   • Spinal cord monitoring
   • Functional evaluation of low back pain

Clinical research

• Fulcrum bending x-ray, fulcrum bending correction index, and its use to determine fusion levels
• Scoliosis maturity markers
• Occupationally related low back pain
• Functional electrical stimulation for paraplegics
• Clinical trials on
  • Super-elastic implant for scoliosis correction
  • Intervertebral disc transplantation
  • Bioactive bone cement
  • Cervical myelopathy

Representative Publications

1. Cheung KMC, Luk KDK. Prediction of scoliosis correction by the fulcrum bending radiograph. J Bone Joint Surg Am 1997, 79: 1144-1150
2. Luk KDK, Ruan DK, Lu DS, Fei ZQ. Fresh frozen intervertebral disc allografting in a bipedal animal model. Spine, May 2003, 28(9): 864-869.
3. Luk KDK, Chow DHK, Holmes A. Vertical instability in spondylolisthesis – a traction radiographic assessment technique and the principle of management. Spine, April 2003, 28(8):819-827.
4. Cheung KMC, Lu WW, Luk KDK, Wong CT, Chan D, Shen JX, Qiu GX, Zheng ZM, Li CH, Liu SL, Chan WK, Leong JCY. Vertebroplasty by use of a strontium containing bioactive bone cement. Spine. Sept 1, 2005. Vol.30, No.17S. S84-S91.
5. Luk KDK, Ng MC, Wong KK, Li G, Lai S, Yang ES, Hu Y. Proton density-weighted spinal fMRI with sensorimotor stimulation at 0.2T. Neuro Image, February 2006, 29(3):995-999.
6. Yeung KWK, Lu WW, Luk KDK, Cheung KMC. Mechanical testing of a smart spinal implant locking mechanism
   based on nickel-titanium alloy. Spine, 15th Sept 2006. Vol 31, no. 20. 2296-2302.
7. Leung VYL, Chan D, Cheung KMC. Regeneration of intervertebral disc by mesenchymal stem cells: Potentials, limitations, and future direction. European Spine Journal. 2006 Aug; 15 Suppl 3:S406-13.
8. Cheung KMC, Senkoylu A, Alanay A, Genc Y, Lau SSN, Luk KDK. Reliability and Concurrent Validity of the Adapted Chinese Version of Scoliosis Research Society-22 (SRS-22) Questionnaire. Spine. 2007 May. Volume 32(10), 1141–1145.
9. Ruan DK, He Q, Ding Y, Hou LS, Li JY, Luk KDK. Intervertebral disc transplantation in the treatment of degenerative spine disease: a preliminary study. Lancet, Mar 2007, 369:993-999.
10. Song YQ, Cheung KMC, Ho DWH, Poon SCS, Chiba K, Kawaguchi Y, Hirose Y, Alini M, Grad S, Yee AFY, Leong JCY, Luk KDK, Yip SP, Karppinen J, Cheah KSE, Sham P, Ikegawa S, Chan D. Association of the Asporin D14 allele with lumbar disc degeneration in Asians. American Journal of Human Genetics, 2008 Mar;82(3):744-7.