Minimally invasive hip replacement surgery has become the catch cry of the past 18 months. The technique of two incision surgery has been touted as allowing safe insertion of hip replacement components and early discharge of patients in comparison to standard procedures. The early results and technique developed by the author are discussed with specific reference to early complications and early radiographic and clinical results.

After extensive cadaveric dissection and anatomical study, a comparison was made of the existing exposures used in two incision surgery including pitfalls and benefits.

Following initial study, a two incision approach has been used on forty patients initially chosen as being suitable for the procedure based upon age, weight, and suitability for cementless hip replacement. Data relating to surgical time, hospital stay, post op complications and radiographic and clinical results have been prospectively analysed.

Early clinical results have been very favourable, including no increase in complication, and earlier discharge and recovery from surgery. The results are being validated by a randomised prospective international study, but the ability to discharge patients within 24 hours of surgery does not appear to be a viable option and possibly not a safe option considering the concerns relating to recovery from anaesthesia and post operative postural hypotension. A radiographic assessment has revealed accurate placement of implants compared to an historic group using conventional exposure.

Clinical scores have been better at six weeks and three months compared to mini incision and standard incision patients.

Further research and experience is required for this technique to be fully applicable and available to the general orthopaedic population. Technically the procedure is more challenging and does require adequate instruction and does have a significant learning curve. However, the early clinical results do support earlier discharge and more rapid recovery compared to standard hip replacement surgery.

Minimally invasive surgery (MIS) for THR may accelerate rehabilitation. The objectives of this study were to determine the effect of 3 surgical approaches (standard, mini (< 10cm), 2 incision Stryker approach (MIS), on length of stay, rehabilitation rates, clinical outcome, quality of life, patient safety, complications and implant position.

This study was conducted in accordance with Good Clinical Practice. Each surgeon completed 6–8 documented cases using the MIS technique before commencing enrolment to eliminate any learning curve effect. Prior to enrolment patients were assessed for eligibility and provided signed informed consent. Patient demographics, medical histories and surgical details were collected. Post-operative rehabilitation was independently documented by a physiotherapist. Clinical evaluations (HHS) were collected pre-operatively, 10 days, 6 weeks, 3 months and 1 year. Patient outcomes (SF 12/WOMAC) were collected pre-operatively and 1 year. Radiological evaluations were completed at 6 weeks. CTs/x-rays were subject to an independent review.

A sample size of 48 patients was determined based on the primary objective – length of stay. Enrolment commenced at the end of 2002 and these results are based on the first cohort of patients; based on current recruitment rates, the authors anticipate that the majority of patients will be enrolled by presentation time.

Preliminary results show mean incision lengths (cm) of 3.5/5.8 for the 2 incision MIS compared to 8.8 and 13.5 for the mini and standard respectively. Mean duration of surgery (mins) was 79 (MIS), 62 (mini) and 42 (standard). The median time (hours:minutes) from end of surgery until the first episode of knee flexion > 45°, straight leg raise, active abduction, standing, out of/in to bed, stair climbing and walking > 20 metres was shortest for MIS compared to mini and standard surgical approaches. The maximum distance walked was greatest for the MIS group. The mean length of stay (days) was shortest for the MIS group. 2.5 compared to 4.7 (mini) and 3.7 (standard).

Mean blood loss (cc) was greatest for the MIS group, 667 compared to 525 (mini) and 467 (standard). There were no intra/post-operative complications or blood transfusions.

Results suggest accelerated rehabilitation, decreased hospital stay and increased surgery duration for the MIS group. There are no safety concerns, however the procedure is felt to be quite technically demanding requiring an appropriate level of training/experience. The authors believe this is the only controlled study of this nature currently being conducted internationally.

Introduction Minimally invasive surgery (MIS) for THR may accelerate rehabilitation. The objectives of this study were to determine the effect of three surgical approaches (standard, mini [< 10 cm], Stryker two incision approach [MIS]) on length of stay, rehabilitation rates, clinical outcome, quality of life, patient safety, complications and implant position.

Methods Each surgeon completed six to eight documented cases using the MIS technique before commencing enrolment to eliminate any learning curve effect. Prior to enrolment patients were assessed for eligibility and provided signed informed consent. Patient demographics, medical histories and surgical details were collected. Post-operative rehabilitation was independently documented by a physiotherapist. Clinical evaluations (HHS) were collected pre-operatively, 10 days, six weeks, three months and one year. Patient outcomes (SF12/WOMAC) were collected pre-operatively and at one year. Radiological evaluations were completed at six weeks. CTs/x rays were subject to an independent review.

Results A sample size of 48 patients was determined based on the primary objective - length of stay. Enrolment commenced at the end of 2002 and these results are based on the first cohort of patients; based on current recruitment rates, the authors anticipate that the majority of patients will be enrolled by presentation time. Preliminary results show mean incision lengths (cm) of 3.5/5.8 for the two incision MIS compared to 8.8 and 13.5 for the mini and standard respectively. Mean duration of surgery (mins) was 79 (MIS), 62 (mini) and 42 (standard). The median time (hours:minutes) from end of surgery until the first episode of knee flexion > 45°, straight leg raise, active abduction, standing, out of/in to bed, stair climbing and walking > 20 metres was shortest for MIS compared to mini and standard surgical approaches. The maximum distance walked was greatest for the MIS group. The mean length of stay (days) was shortest for the MIS group, 2.5 compared to 4.7 (mini) and 3.7 (standard). Mean blood loss (cc) was greatest for the MIS group, 667 compared to 525 (mini) and 467 (standard). There were no intra/post-operative complications or blood transfusions.

Conclusion Results suggest accelerated rehabilitation, decreased hospital stay and increased surgery duration for the MIS group. There are no safety concerns, however the procedure is felt to be quite technically demanding requiring an appropriate level of training/experience. The authors believe this is the only controlled study of this nature currently being conducted internationally.

In relation to the conduct of this study, one or more of the authors has received, or is likely to receive direct material benefits.