title: The use of computer navigation in performing minimally invasive surgery for intertrochanteric hip fractures--The experience in Singapore.
abstract: OBJECTIVE
  Intertrochanteric hip fractures are very common and early mobilisation correlates with a better outcome. The ideal surgical procedure should protect the soft tissue envelope, thereby preserving blood supply and reducing blood loss. Furthermore, occupational exposure to fluoroscopy that is used in hip fracture fixation remains a concern amongst orthopaedic surgeons. Computer-aided surgery can help to reduce reliance on fluoroscopy. We therefore combined the principles of minimally invasive plate osteosynthesis (MIPO) and computer navigation to describe a new procedure. We also present our results using this technique of minimally invasive computer-navigated dynamic hip screw fixation (navMIS-DHS), and compare it to computer-navigated open DHS fixation (nav-DHS) and to conventional open DHS fixation (conv-DHS).
  
  
  METHODS
  This paper has three parts. In the first part, we describe the procedure of navMIS-DHS in detail. In the second part, we present our initial retrospective pilot series of 35 cases. Amongst them we performed 5 navMIS-DHS, 3 nav-DHS and 27 conv-DHS. There were also two cases of conv-DHS deliberately performed with a mini-incision in an attempt to see if we could duplicate the 5 cm incision that we achieved with navMIS-DHS. All patients were followed up for a minimum of 6 months. In the third part, we performed a single surgeon prospective evaluation of navMIS-DHS versus conv-DHS involving 43 fractures in two arms.
  
  
  RESULTS
  We were able to achieve reduction in fluoroscopy time. There was also reduction in opiate requirement post-operatively in the minimally invasive procedure. The incision sizes were also smaller. The prospective study also showed less wound-related complications in navMIS-DHS and a shorter time to ambulation. Implant positions were acceptable but we have also described how it may be improved.
  
  
  CONCLUSIONS
  Navigated MIS-DHS, by virtue of less pain, better healing, earlier rehabilitation and potentially shorter hospital stay, would benefit both the patients and reduce the economic strain on the health care system. It is a safe and reproducible procedure. Technical difficulties are present and these need to be addressed with further modifications of technique, and instrumentation.
authors.affiliation: Department of Orthopaedic Surgery, Trauma Service, Singapore General Hospital, Outram Road, Singapore 169608, Singapore. keenwai@gmail.com
authors.forename: K W
authors.initials: KW
authors.lastname: Chong
authors.forename: M K
authors.initials: MK
authors.lastname: Wong
authors.forename: I S
authors.initials: IS
authors.lastname: Rikhraj
authors.forename: T S
authors.initials: TS
authors.lastname: Howe
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001863:Bone Screws; D005260:Female; D005471:Fluoroscopy; D005500:Follow-Up Studies; D005593:Fracture Fixation, Internal / Q000379:methods*; D006620:Hip Fractures / Q000000981:diagnostic imaging / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures; D011446:Prospective Studies; D012189:Retrospective Studies; D025321:Surgery, Computer-Assisted; D013997:Time Factors; D016896:Treatment Outcome