Comparison of gait in patients following a computer-navigated minimally invasive anterior approach and a conventional posterolateral approach for total hip arthroplasty: a randomized controlled trial. Comparative study between computer assisted-navigation and conventional technique in minimally invasive surgery total knee arthroplasty, prospective control study. Midterm outcomes of electromagnetic computer-assisted navigation in minimally invasive total knee arthroplasty New two-incision minimally invasive total hip arthroplasty: comparison with the one-incision method Minimally Invasive versus Classic Procedures in Total Hip Arthroplasty: A Double-blind Randomized Controlled Trial Time course and extent of functional recovery during the first postoperative year after minimally invasive total hip arthroplasty with two different surgical approaches--a randomized controlled trial. Reduction in variability of acetabular cup abduction using computer assisted surgery: a prospective and randomized study. Computer-assisted total knee arthroplasty using mini midvastus or medial parapatellar approach technique Five-year follow-up of minimally invasive computer assisted total knee arthroplasty (MICATKA) versus conventional computer assisted total knee arthroplasty (CATKA) - A population matched study. Tackling the learning curve: comparison between the anterior, minimally invasive (Micro-hip®) and the lateral, transgluteal (Bauer) approach for primary total hip replacement Early thromboembolic events ≤1week after fast-track total hip and knee arthroplasty. Myocardial infarction following fast-track total hip and knee arthroplasty—incidence, time course, and risk factors: a prospective cohort study of 24,862 procedures Surgical access and damage extent after total hip arthroplasty influence early gait pattern and guide rehabilitation treatment. Robot‐assisted total hip arthroplasty: Clinical outcomes and complication rate Minimal invasive and computer-assisted total knee replacement compared with the minimal invasive technique: a prospective, randomized trial with short-term outcomes Minimally invasive total hip arthroplasty--our clinical experience. Minimal-invasive posterior approach for total hip arthroplasty versus standard lateral approach. Minimally invasive intermuscular approach does not improve outcomes in bipolar hemiarthroplasty for femoral neck fracture Radiographic Analysis of One-level Minimally Invasive Transforaminal Lumbar Interbody Fusion (MI-TLIF) With Unilateral Pedicle Screw Fixation for Lumbar Degenerative Diseases Comparison of radiographic alignment of imageless computer-assisted surgery vs conventional instrumentation in primary total knee arthroplasty. Antero-lateral minimal invasive (ALMI) approach for total hip arthroplasty technique and early results Randomized trial of computer-assisted knee arthroplasty: impact on clinical and radiographic outcomes. Mini-incision versus mini-incision and computer-assisted surgery in total knee replacement: a radiological prospective randomised study.
Minimally invasive total hip arthroplasty ( MIS THA ) aims at minimizing damage to muscles and tendons to accelerate postoperative recovery . Computer navigation allows a precise prosthesis alignment without complete visualization of the bony l and marks during MIS THA . A r and omized controlled trial ( RCT ) was conducted to determine the effectiveness of a computer-navigated MIS anterior approach for THA compared to a conventional posterolateral THA technique on the restoration of physical functioning during recovery following surgery . Thirty-five patients underwent computer-navigated MIS THA via the anterior approach , and 40 patients underwent conventional THA using the conventional posterolateral approach .  Gait analysis was performed preoperatively , 6 weeks , and 3 and 6 months postoperatively using a body-fixed-sensor based gait analysis system . Walking speed , step length , cadence , and frontal plane angular movements of the pelvis and thorax were assessed . The same data were obtained from 30 healthy subjects . No differences were found in the recovery of spatiotemporal parameters or in angular movements of the pelvis and thorax following the computer-navigated MIS anterior approach or the conventional posterolateral approach . Although gait improved after surgery , small differences in several spatiotemporal parameters and angular movements of the trunk remained at 6 months postoperatively between both patient groups and healthy subjects BACKGROUND Both Minimally Invasive surgery ( MIS ) and Computer-Assisted Surgery ( CAS ) are useful in Total Knee Arthroplasty ( TKA ) . Minimally invasive total knee arthroplasty was associated with decreased blood loss , shorter hospital stays , and increased range of motion .  Computer-assisted surgery in total knee arthroplasty was developed to improve the positioning of implants during surgery . OBJECTIVE To evaluate radiographic results relative to component position and limb alignment when using a navigation system compared with conventional technique in MIS-TKA . MATERIAL AND METHOD A prospect i ve control study was performed in 180 patients who underwent total knee arthroplasty by one surgeon . All patients were r and omly divided into two groups , Conventional and Navigation TKA .  Intra- , post-operative data , and postoperative limb alignment were recorded for comparison in both groups . RESULTS The postoperative mechanical axis was within 3 degrees of neutral mechanical alignment in 94 % of the navigation group and 87 % in conventional group ( p = 0.13 ) . Registration time of navigation group is 13.58 minutes . No statistical significant difference was found in tourniquet time and postoperative blood loss in both groups . CONCLUSION The use of navigation in total knee arthroplasty increases accuracy in limb and implants alignment , and does not increase complications and surgical times Background A combination of two emerging technologies , computer-assisted navigation and minimally invasive surgery , in total knee arthroplasty has gained increasing interests from orthopedic surgeons around the world . To date , there has never been any midterm study for clinical and radiographic outcomes from using an electromagnetic computer-assisted navigation system . In this study , we aim ed to systematic ally compare clinical and radiographic outcomes of minimally invasive surgery in total knee arthroplasty ( MIS-TKA ) performed with and without electromagnetic computer-assisted navigation at immediate and midterm follow-ups . Methods A total of 151 patients ( 160 knees ) who underwent MIS-TKA were r and omized to be operated with electromagnetic computer-assisted navigation ( group I : 75 patients , 80 knees ) or without the navigation ( group II : 76 patients , 80 knees ) . The clinical and radiographic outcomes of immediate , 6-week postoperative follow-up and average 6.1-year follow-up were compared . Results On immediate , 6-week postoperative follow-up , clinical and radiographic outcomes did not reveal any difference between the two groups except for the fact that the operative time was longer in the navigation group . On 6.1-year follow-up , a total of 58 patients ( 63 knees ) from group I and 58 patients ( 61 knees ) from group II were reevaluated . There were no significant differences in clinical and radiographic loosening and in complications between the two groups . Conclusion In this study , no significant differences of clinical and radiographic outcomes were found for immediate and midterm follow-ups of MIS-TKA performed with and without electromagnetic computer-assisted navigation except for the additional operating time in the navigation group Background There has been increasing interest in performing total hip arthroplasty ( THA ) with minimally invasive surgery ( MIS ) . This study was conducted to examine the effectiveness of MIS-THA using the new two-incision technique versus the one-incision technique . Methods A consecutive series of 113 patients who underwent MIS-THAs ( 63 one-incision cases , 50 two-incision cases ) were studied .  One-incision THA was performed with a posterolateral approach . For the two-incision , the first incision for cup insertion was made over the anterolateral side of the hip . Intermuscular dissection was performed between the gluteus medius and the tensor fascia lata . The second incision , for stem insertion , was made on the posterolateral side of the hip along the fiber of the gluteus maximus . Intermuscular dissection was made between the gluteus medius and the piriformis . Results Postoperative rehabilitation was significantly more rapid in the new two-incision group compared to the group with one incision . Postoperatively , the Harris Hip Score and the Western Ontario and the McMaster Universities Osteoarthritis Index score were significantly different between the two groups , especially the functional sections . Conclusions The findings of this study show that our new two-incision MIS-THA is an excellent surgical modality that allows early rehabilitation Background For total hip arthroplasty ( THA ) , minimally invasive surgery ( MIS ) uses a smaller incision and less muscle dissection than the classic approach ( CLASS ) , and may lead to faster rehabilitation . Questions / purpose sDoes minimally invasive hip arthroplasty result in superior clinical outcomes ? Patients and Methods In this double-blind r and omized controlled trial , 120 consecutive primary noncemented THAs in 120 patients were assigned to one of two groups ( MIS or CLASS ) . The r and omization sequence was stratified for two groups of surgeons , ie , those using a posterolateral approach ( PL-CLASS or PL-MIS ) and those using an anterolateral approach ( AL-CLASS or AL-MIS ) . Length of the incisions was 18 cm for the CLASS procedures . MIS incisions were extended at the skin level to 18 cm at the end of the procedure . The primary end point was the Harris hip score ( HHS ) at 6 weeks postoperatively . Patient-centered question naires were obtained preoperatively and after 6 weeks and 1 year . Results For the patients in the MIS group ( average 7.8 cm incision length ) , statistically significant increased mean HHSs were seen compared with the CLASS group at 6 weeks and 1 year . This difference was small and mainly caused by the favorable results of the PL-MIS . In the MIS group , surgical time was longer . A learning curve was observed based on operation time and complication rate . Although not statistically significant , the perioperative complication rate was rather high in the ( anterolateral ) MIS group . Conclusions The minimal invasive approach in THA did not show a clinical ly relevant superior outcome in the first postoperative year . Level of Evidence Level I , therapeutic study . See Guidelines for Authors for a complete description of levels of evidence UNLABELLED While others have reported short-term comparisons between various minimally invasive surgical ( MIS ) approaches to  total hip arthroplasty ( THA ) and their conventional analogues , longer-term data is lacking , as is information indicating whether MIS approaches to THA provide a biomechanically complete recovery . Furthermore , different MIS approaches have not been compared . Our approaches of interest were a one-incision modified Watson-Jones , and a two-incision approach . HYPOTHESES ( 1 ) There are significant differences in gait recovery patterns between the two surgical groups and ( 2 ) THA subjects have significant differences in function one year after surgery compared to control subjects . To test these hypotheses , THA c and i date s ( n=26 ) were r and omized to receive one of these MIS approaches and evaluated preoperatively , and postoperatively at 3 weeks , and at 3 , 6 and 12 months . Evaluations included three-dimensional gait analysis and 24-hour step-counts . The same data were obtained from 25 control subjects .  Recovery time-course was assessed using repeated measures ANOVA . T-tests were used to compare controls with the pooled group of THA subjects . We found no differences between the two THA surgical groups regarding the time-course of recovery ( p≥0.591 ) . Although recovery was statistically complete by 3 months postoperatively for all variables , there were significant differences from controls at 12 months . Most notably , the external hip adduction moment , which reflects hip abductor function , was more than one st and ard deviation below normal ( p<0.001 ) . THA subject inactivity could not explain the gait differences , since one year after surgery daily step counts were not significantly different from controls ( p=0.346 ) . More work is necessary to determine ways to improve biomechanical outcomes for today 's patients with high expectations for function and implant longevity Optimal orientation of the acetabular component of a  total hip prosthesis  is an important factor in determining the early and long-term result of a  total hip arthroplasty ( THA ) . Conventional positioning of the cup component is usually done using a free-h and method , or with the help of a mechanical acetabular alignment guide . However , these methods have proven to be inaccurate , and a great variation in orientation of the cup is found postoperatively . In this study , we wished to determine if the variability of the abduction angle of acetabular cups could be reduced with the use of computer navigation . The abduction angles of the acetabular components of three groups of 50 THAs were assessed . In the first group , a free-h and method was used to position the cup component . This group was operated in the period before we started using computer navigation for hip surgery . In the second group , CT-based computer navigation was used to plan and help position the cup . The third group consisted of 50 THA cases in which a free-h and method was used to position the cup , although these procedures were performed in the period after we had begun using the Computer Assisted Surgery ( CAS ) system . The variability in cup abduction angle was assessed in all three groups and compared . There was a significant reduction in variability in the CAS group compared to the first group . There was also a reduction in variability in the CAS group compared to the third group , although this was not statistically significant . It is concluded that the use of computer navigation helped the surgeon to place the cup component with less variability of the abduction angle , and , more importantly , we found that no cups were placed in the more extreme positions ( outliers ) Background Despite the growing evidence in the literature there is still a lack of consensus regarding the use of minimally invasive surgical technique ( MIS ) in total knee arthroplasty ( TKA ) . Methods A prospect i ve , r and omized , international multicentre trial including 69 patients was performed to compare computer-assisted TKA ( CAS-TKA ) using either mini-midvastus ( MIS group ) or st and ard medial parapatellar approach ( conventional group ) .  Patients from 3 centers ( Maastricht , Zwickau , Adelaide ) with end-stage osteoarthritis of the knee were r and omized to either an MIS group with dedicated instrumentation or a conventional group to receive cruciate retaining CAS-TKA without patella resurfacing .  The primary outcome was to compare post operative pain and range of motion ( ROM ) . The secondary outcome was to measure the duration of surgery , blood loss , chair rise test , quadriceps strength , anterior knee pain , Knee Society Score (KSS),WOMAC scores , mechanical leg axis and component alignment . Results Patients in the MIS group ( 3.97 ± 2.16 ) had significant more pain at 2 weeks than patients in the conventional group ( 2.77 ± 1.43 ) p = 0.003 . There was no significant difference in any of the other primary outcome parameters . Surgery time was significantly longer ( p < 0.001 ) and there were significantly higher blood loss ( p = 0.002 ) in the MIS group as compared to the conventional group . The difference of the mean mechanical leg alignment between the groups was not statistically significant ( –0.43 ° ( 95 % CI –1.50 – 0.64 ) ; p = 0.43).There was no significant difference of component alignment between the two surgical groups with respect to flexion/extension ( p = 0.269 ) , varus/valgus ( p = 0.653 ) or rotational alignment ( p = 0.485 ) of the femur component and varus valgus alignment ( p = 0.778 ) or posterior slope ( p = 0.164 ) of the tibial component . Conclusion There was no advantage of the MIS approach compared to a conventional approach CAS-TKA in any of the primary outcome measurements assessed , however the MIS approach was associated with longer surgical time and greater blood loss . MIS-TKA in combination with computer navigation is safe in terms of implant positioning . Trial registration number Clinical Trials.gov NCT02625311 8 December BACKGROUND Minimally invasive surgery ( MIS ) has perceived advantages in the early post-operative stage such as reduced blood loss , decreased pain , earlier return to function and earlier discharge . The aim of our study was to confirm that longer term clinical outcome of TKA is not compromised when MIS is combined with computer assisted surgery . METHODS Eighty patients matched for age , gender , pre-operative Knee Society Score ( KSS ) and mechanical axis were prospect ively studied . Forty patients underwent minimally invasive computer assisted total knee arthroplasty ( MICATKA ) and 40 patients underwent conventional computer assisted TKA ( CATKA ) .  Functional scores were determined at 6 weeks , 6 , 12 , 18 , and 24 months and 5 years post-surgery . Long-leg alignment views were obtained 3 months post-operatively . RESULTS KSSs in the short term were significantly better in the MICATKA group than in the CATKA group ( p<000.1 ) . Tourniquet-time was 58 min in the MICTKA group and 60 min in the CATKA group ( p=0.3 ) . Straight leg raise was achieved by day one in 93 % of the MICATKA group compared to 30 % of the CATKA group ( p<0.001 ) . Length of stay for the MICATKA group has a mean of 3.25 days and a mean of 6 days for the CATKA group ( p<0.001 ) . KSSs up to 2-years were significantly better in the MICTKA group ( p<0.001 ) . At 5-years there was no significant difference in KSSs ( p=0.46 ) in the MICATKA and CATKA groups . CONCLUSION We confirm that the use of navigation in minimally invasive TKA permits a number of early post-operative advantages and that longer-term functional outcome is not compromised with its usage . LEVEL OF EVIDENCE Level II Background and purpose There is still conflicting evidence about the true benefit of minimally invasive ( MI ) techniques in total hip replacement ( THR ) . The aim of this prospect i ve study was to evaluate the safeness of a MI approach during the learning curve of a single surgeon . Second , clinical and radiographic results among the  MI THR group were compared with the results using a st and ard transgluteal ( Bauer ) approach . Methods 86 primary unilateral total hip arthroplasties ( THAs ) through a MI , anterior ( Micro-hip ® ) approach were performed by a single senior surgeon ( ES ) , representing a consecutive series of patients after beginning with the MI technique . Cases were compared to a matched cohort of patients who were treated with a st and ard transgluteal ( Bauer ) approach .  Operation time , incision length , perioperative blood loss , haemoglobin level and blood transfusions were monitored . Complications were documented and followed up 1 year postoperatively . The Harris Hip Score ( HHS ) , range of motion , use of analgetics , the Trendelenburg sign , sensibility of the lateral femoral cutaneous nerve and the acetabular/femoral component placement as well as potential heterotopic ossifications were analysed in both the groups after 12 months postoperatively . Results 74 MI THR patients and 60 st and ard THR patients were available for the one year follow-up . Operative time was significantly longer in the MI group , reduction in the haemoglobin level during the first 24 h was significant and the length of skin incision was significantly shorter . No significant differences were found for HHS , range of motion , use of analgetics , the Trendelenburg sign , and the acetabular/femoral component placement , heterotopic ossifications and intra- and postoperative complications . Sensibility of the lateral femoral cutaneous nerve was affected in three patients in the MI group . Radiographic evaluation revealed no component migration , implant subsidence or radiolucency signs in both the groups . DicussionConsistent with recent meta- analysis we found reduced blood loss , similar clinical /radiographic outcome and similar complication rates compared to st and ard THA . Our study shows , that MI THR is a safe procedure during the learning curve of an experienced surgeon INTRODUCTION Thromboembolic events ( TEE ) are serious complications after total hip ( THA ) and knee arthroplasty ( TKA ) , with reported in-hospital incidences of about 0.5 - 1 % for venous thromboembolic events ( VTE ) and 0.2 % for myocardial infa rct ions ( MI ) and stroke . However , little data exist on in-hospital TEE when using a st and ardized fast-track protocol with early mobilization . MATERIAL S AND METHODS A large detailed cohort study in primary unilateral THA and TKAs on " early " ( in-hospital or after discharge but within 1week of surgery ) and 30-days TEEs , including prospect i ve recording of patient characteristics , complete follow-up through the Danish National Patient Register , and detailed evaluation on disposing factors and consequences of " early " TEEs through review of medical records . RESULTS In 13,775 procedures with a median LOS of 2days , 43 ( 0.32 % ; 95 % CI : 0.23 - 0.42 ) " early " and 90 ( 0.65 % ; 95 % CI : 0.53 - 0.80 ) 30-day TEEs were recorded . " Early " TEEs consisted of 9 ( 0.07 % ; 95 % CI : 0.04 - 0.13 ) MI , 10 ( 0.08 % 95 % CI : 0.04 - 0.13 ) strokes , 13 ( 0.09 % ; 95 % CI : 0.05 - 0.16 ) pulmonary embolisms and 11 ( 0.08 % ; 95 % CI : 0.04 - 0.15 ) deep venous thromboses . Most TEEs were in patients with irreversible dispositions ( e.g. previous TEE , high age and cardiac disease ) , but 5 of 9 MIs were associated with postoperative anemia . All in-hospital VTE ( n : 16 ) occurred while patients received recommended thromboprophylaxis . CONCLUSIONS Incidence of " early " TEEs after fast-track THA and THA is low , but MIs may be further reduced by improving perioperative treatment of anemia . Further research is needed regarding interventions for prevention of " early " TEE in disposed patients Background and purpose — Acute myocardial infa rct ion ( MI ) is a leading cause of mortality following total hip and knee arthroplasty ( THA/TKA ) . The reported 30-day incidence of MI varies from 0.3 % to 0.9 % . However , most data derive from administration and insurance data bases or large RCTs with potential confounding factors . We studied the incidence of and potential modifiable risk factors for postoperative MI in a large , multicenter optimized “ fast-track ” THA/TKA setting . Patients and methods — A prospect i ve cohort study was conducted on consecutive unselected elective primary unilateral THA and TKA  , using prospect i ve information on comorbidities and complete 90-day follow-up from the Danish National Patient Registry . Evaluation of discharge summaries and medical records was undertaken in cases of suspected MI . Logistic regression analyses were carried out for identification of preoperative risk factors . Results — Of 24,862 procedures with a median length of stay 2 ( IQR 2–3 ) days , 30- and 90-day incidence of MI was 31 ( 0.12 % ) and 48 ( 0.19 % ) . Preoperative risk factors for MI ≤30 days were age > 85 years ( OR 7.4 , 95 % CI 2.3–24 ) , insulin-dependent diabetes mellitus ( IDDM ) ( 3.6 , CI 1.1–12 ) , cardiovascular disease ( 2.4 , CI 1.1–5.0 ) and hypercholesterolemia ( 2.3 , CI 1.1–5.1 ) . Of 31 patients with MI ≤30 days 9 were treated with vasopressors for intraoperative hypotension and 27 had postoperative anemia . Interpretation — Fast-track THA and TKA had a low 30-day MI incidence . Focus on patients with age > 85 , IDDM , cardiovascular disease , and hypercholesterolemia may further reduce the 30-day incidence of MI . The role of postoperative anemia and intraoperative hypotension are other areas for further AIM Different surgical approaches are used in total hip arthroplasty . The present study confronted two surgical techniques , analysing functional recovery in terms of activities of daily living , and ambulation using gait analysis , after a st and ardized rehabilitation protocol . Our hypothesis was that the increased surgical damage could modify the gait pattern and functional recovery . METHODS Thirty patients were r and omly assigned to two homogeneous groups : Group A was treated with intermuscular minimally invasive surgery ( MIS ) ; Group B was treated with st and ard lateral transmuscular approach . Follow up was planned at 30 and 90 days . Instrumental evaluation using gait analysis and functional evaluation using vali date d scales were performed at follow up . RESULTS No differences could be found as for functional scales . At the first follow up , the MIS approach proved to be the most favourable : data showed a longer duration of the swing phase , an improved range of motion of the non-treated hip , a reduced adduction ( all P<0.005 ) and a correct timing of activation of the gluteus medium muscle on the treated side . At the second evaluation , gait analysis demonstrated some benefits of the intermuscular approach ( a better flexion of both hips , and a minor obliquity of the pelvis during the terminal stance ) , but also advantages in the transmuscular group ( better hip extension ) . CONCLUSION Gait pattern after THA seems to be strictly dependent on surgical access and on the extent and location of surgical damage . It appears important to consider these elements in order to correctly manage the rehabilitation treatment after surgery BACKGROUND The purpose of this study was to report minimum 2-year outcomes and complications for robotic-arm-assisted total hip arthroplasty ( THA )  . METHODS Data were prospect ively collected and retrospectively review ed between June 2011 and April 2014 . Inclusion criteria were primary robotic-arm-assisted THAs treating idiopathic osteoarthritis with ≥ 2-year follow-up .  Demographics , operating time , complications , 2-year outcome scores and satisfaction , and subsequent surgeries were recorded . RESULTS There were 181 cases eligible for inclusion , of which 162 ( 89.5 % ) had minimum 2-year follow-up . At the latest follow-up , the mean visual analogue scale was 0.7 , satisfaction was 9.3 , Harris hip score was 91.1 and forgotten joint score was 83.1 . Six ( 3.7 % ) intraoperative complications and six ( 3.7 % ) postoperative complications were reported . No leg length discrepancies ( LLDs ) or dislocations were reported . CONCLUSIONS Robotic-arm-assisted THA demonstrates favourable short-term outcomes and does not result in a higher complication rate compared to non-robotic THA as reported by the literature Abstract Introduction Up to now , no prospect i ve , r and omized comparisons between minimal invasive and computer-assisted total knee arthroplasty ( MICA-TKA ) , and minimal invasive technique ( MI-TKA ) has been documented to evaluate not only clinical , but also radiologic results of the MICA-TKA . This prospect i ve , r and omized study was performed to compare the short-term results of MICA-TKA with minimal invasive technique MI-TKA for 6-month follow-up . Patients and methods We reported the clinical and radiological results of 80 subjects who had cruciate-substituting , TKA-implanted primary total knee arthroplasties using either minimal invasive and computer-assisted technique ( 40 patients Group I ) or minimal invasive technique ( 40 patients , Group II ) .  Tourniquet time , length of skin incision , and total blood loss were compared . Knee society scores ( KSSs ) , knee society functional scores ( KSFSs ) , range of motion ( ROM ) , and radiographic results were assessed and reported preoperatively and at 6-month follow-up . Results The accuracy of the implantations in relation to the coronal mechanical axis in Group I was superior to that of Group II ( P < 0.05 ) . The femoral rotational profile revealed the prosthesis in Group I that was implanted with significantly less internal rotation than in Group II . The average blood loss in patients of Group I was significantly reduced as compared to patients of Group II . No significant difference was detected in terms of tourniquet time or length of skin incision . Clinical results , with regard to ROMs and KSSs , as well as KSFSs were equally good in both the groups . Conclusions Better alignment and similarity of good clinical results at short-term follow-up may provide subjects who receive MICA-TKA with long-term endurance of their implants . Further studies on longer-term outcomes and functional improvements are required to vali date these possibilities BACKGROUND Minimally invasive prosthetic hip surgery ( MIS ) attempts to minimise the extent of the operation . The aim of the study was to describe minimally invasive hip surgery and to present early clinical experience of the authors . MATERIAL AND METHODS 41 minimally invasive hip replacements through a posterior approach were carried out at the Orthopaedic Department of the Postgraduate Medical Education Centre in Otwock between 2004 and 2006 . 29 of those patients were included into the study , of whom 23 presented for follow-up . A control group consisted of 29 r and omly selected patients operated on using the classical method . Patients qualified for MIS had a BMI below 30 and a structurally normal hip joint with a good range of motion .  RESULTS Early results were subjected to a statistical analysis of 20 parameters . CONCLUSION 1 . The analysis showed that statistically significant baseline differences between MIS and traditionally treated patients included only BMI scores , structure of the hip joint and range of motion . 2 . Implantation of a hip endoprosthesis in a MIS procedure does not differ from the traditional operation utilising a posterior access except for skin incision length In this prospect i ve study we compared clinical and radiological results and rehabilitation progress of 64 patients who underwent total hip arthroplasty using the st and ard lateral approach with 64 patients operated with a minimal-invasive ( MIS ) posterior approach .  The outcome of our study did not show any significant differences with regard to patient 's safety such as complication rate and radiological assessment of the cup position . There was no difference in the duration of surgery , blood loss , hospital stay and postoperative leg length discrepancy . Rehabilitation milestones were achieved earlier by MIS patients and three and six months postoperatively , the Harris Hip Score of the MIS group was significantly higher Background Minimally invasive surgery ( MIS ) can lead to early recovery , but its postoperative effect is short after total hip arthroplasty for osteoarthritis . Because bipolar hemiarthroplasty ( BHA ) for femoral neck fractures is preferred for elderly patients , early functional recovery may prevent the rapid progression of disuse atrophy , and an MIS surgical approach may improve subsequent hip joint function . Methods MIS-BHA was performed using the direct anterior approach , without muscle or tendon detachment . A total of 83 patients who underwent BHA from April 2007 to February 2009 were assigned to MIS-BHA or conventional BHA . Selection of patients for MIS-BHA was not r and omized . Hip joint function was evaluated with the Hospital for Special Surgery ( HSS ) system at 1 month and 1 year after surgery . Results There were no significant differences in age , sex , height , weight , body mass index , time from admission to surgery , or preinjury HSS scores between two groups . HSS scores were higher with MIS-BHA ( 24.2 vs. 20.2 ; P = 0.01 ) at 1 month but were similar 1 year after surgery ( 29.9 vs. 27.2 ; P = 0.10 ) . Conclusions The effectiveness of MIS-BHA for femoral neck fracture is limited to the early postoperative period . Therefore , MIS-BHA does not appear to be appropriate for treatment of femoral neck fractures Study Design : A prospect i ve r and omized study was conducted . Objective : The purpose of this study was to assess the radiographic outcomes of one-level minimally invasive transforaminal lumbar interbody fusion ( MI-TLIF ) with unilateral pedicle screw instrumentation for degenerative lumbar spine disease . Summary of Background Data : MI-TLIF has become an increasingly popular method of lumbar arthrodesis . Recent technological advances in spinal instrumentation have culminated in the development of MI-TLIF with unilateral pedicle screw fixation . However , there are few published studies on radiographic outcomes of the MI-TLIF with unilateral pedicle screw fixation . Methods : A total of 65 patients with one-level degenerative lumbar spine disease were enrolled in this study . Patients were r and omized into the unilateral or bilateral fixation group based on a computer-generated number list . Thirty-one patients ( 17 men and 14 women ; average age , 57.3 y ) were r and omized to the unilateral group ( group A ) and 34 patients ( 16 men and 18 women ; average age , 58.9 y ) to the bilateral group ( group B ) . All patients underwent minimally invasive decompression , interbody fusion , and pedicle screw fixation with the assistance of microscopic tubular retractor system ( METRx-MD ) and Sextant system . All patients were asked to follow-up at 3 , 6 , and thereafter once every 6 months after surgery . The visual analog scale ( VAS ) , Oswestry disability index ( ODI ) , and modified Prolo ( mProlo ) scores were obtained for all patients 24 hours before the operation and at each follow-up visit . The whole lumbar lordosis ( WL ) , the segmental lordosis ( SL ) , fusion level disk space angle , lumbar scoliosis angle , and segmental scoliosis angle were determined before and after surgery on st and ard x-rays . The disk height index ( DI ) and the lumber curvature index ( LI ) were also evaluated . Results : The mean follow-up was 26.6 months , with a range of 18–36 months . All patients showed evidence of fusion at 12 months postoperatively . Statistically , there was no significant difference between the 2 groups in terms of demographic data . The average postoperative VAS , ODI , and mProlo scores improved significantly in each group . No significant differences were found between the 2 groups in relation to VAS , ODI , and mProlo scores at each follow-up time point . There were no significant differences between the 2 groups in relation to WL , SL , disk space angle , lumbar scoliosis angle , segmental scoliosis angle , DI , and LI . There was also no difference between postoperative different follow-up visits in terms of these radiographic parameters in both groups . There was a positive linear correlation between the LI and WL in both groups . Conclusions : One-level unilateral pedicle screw instrumented MI-TLIF provided similar radiologic and clinical outcomes to bilateral pedicle screw instrumented MI-TLIF . This study showed that MIS-TLIF with unilateral pedicle screw fixation would be sufficient in the management of preoperatively stable patients with lumbar degenerative disease A total of 208 patients were enrolled in a multicenter , prospect i ve r and omized , institutional review board-approved study that compared preoperative surgical plan to postoperative 2-dimensional radiographic alignment measured by a blinded review er for  primary total knee arthroplasty ( TKA ) implanted using computer-assisted surgery ( CAS ) compared with conventional TKA instrumentation . The results demonstrated a statistically significant improvement in the coronal tibial component alignment ( P < .03 ) and failed to demonstrate a statistically significant improvement in the mechanical axis , femoral coronal/sagittal , and tibial sagittal alignment . Knee Society Score knee and function scores and 6-minute walk test were equivalent between the 2 treatment groups at all postoperative intervals . There was a statistically significant increase in the skin-skin time ( P < .0001 ) and the time until first bone cut ( P < .0001 ) for the CAS knees compared with those implanted with conventional instrumentation . The use of CAS in this r and omized clinical trial conducted at high-volume centers did not offer a clinical ly meaningful improvement in postoperative alignment , clinical , functional , or safety outcomes compared with conventional TKA Introduction : Minimally invasive surgery represents one of the most recent techniques to have emerged within THA . In conventional THA , the incision typically measures 15–20 cm . Minimal invasive approach defined as less invasive to the skin , muscles , or bone may reduce complications and improve recovery time . A number of different approaches and methods have been described in literature . Purpose : This is a prospect i ve study describing the technique and early results of the modified antero-lateral minimal invasive ( ALMI ) approach and comparing our results to the results of other investigators interested in minimal invasive THA . Material s and methods : Seventy-five consecutive primary total hip arthroplasties ( cemented and cementless ) were done through a modified ALMI approach ( 6–8 cm ) , in which we kept the hip abductors intact . Neither special instruments nor specially design ed prostheses were needed . Minimum follow-up was 12 months . Results : The mean Harris hip score for patients after 12-month follow-up was 90 while the mean Merle d’Abugine mean score was 16.5 . Both scores reached almost the maximum values within 3 months after surgery . The cup abduction angle for 70 % patients was between 35 ° and 45 ° . No femoral stem mal-alignment was recorded . The mean operative time of cemented prosthesis was 65 min while that of the cementless prosthesis was 55 min . No wound complications or dislocations were recorded . All the patients were allowed to weight bear in the second post-operative day and involved in an early rehabilitation program . Conclusion : ALMI hip approach with sparing of hip abductors is safe and gives excellent orientation for positioning of prosthesis components . It also allows early and smooth post-operative rehabilitation with fast recovery of the patient in terms of weight bearing Computer-assisted surgery in knee arthroplasty is gaining popularity ; however , the result ing outcome improvement is controversial . A double-blinded trial was performed with subjects r and omized to undergo surgery with either computer-assisted or nonassisted instruments .  Postoperatively , limb and implant alignment and rotation were assessed using both full-length radiographs and computed tomography in addition to clinical scores . One hundred twenty patients ( 141 knees ) were r and omized . No differences in Western Ontario MacMaster Osteoarthritis Score , Short Form-36 , or flexion were seen . More varus limb alignment was seen in the computer-assisted group ( 1.9 ° ) vs the nonassisted group ( 0.9 ° , P = .04 ) with no improvement in alignment precision . Rotational alignment of the components did not differ between groups . Computer-assisted surgery appeared to have minimal effect on knee implant arthroplasty with no improvement in limb alignment or early functional outcome The aim of this trial was to compare the radiological results of 74 patients undergoing a mini-invasive total knee replacement ( TKR ) using either a traditional alignment guide ( MIS group ) or a computer assisted alignment system ( MICA group ) . All the patients were prospect ively r and omised to either group and the same implant was used for both groups . At 8 months post-operatively , the frontal femoral component angle ( FFC ) , the frontal tibial component angle ( FTC ) , the hip-knee-ankle angle ( HKA ) and the sagittal orientation of components ( slopes ) were evaluated respectively . The slopes of the femoral component and the FTC angle were statistically better aligned in the MICA group ( p<0.001 ) . The MICA group showed both a significant fewer number of outliners and a significant higher number of implants with all five radiological parameters ideally aligned . The operative time was statistically longer in the computer assisted group
Strong evidence was found for a decrease in operative time and intraoperative blood loss for MIS THA , with no difference in complication rates and risk for acetabular outliers .
Strong evidence exists that there is no difference in physical functioning , measured either by question naires or by gait analysis .
Moderate evidence was found for a shorter length of hospital stay after MIS THA .
Conflicting evidence was found for a positive effect of MIS THA on pain in the early postoperative period , but that effect diminished after three months postoperatively .
Strong evidence was found for an increase in operative time for CAS THA , and limited evidence was found for a decrease in intraoperative blood loss .
Furthermore , strong evidence was found for no difference in complication rates , as well as for a significantly lower risk for acetabular outliers .
Conclusions The results indicate that MIS THA is a safe surgical procedure , without increases in operative time , blood loss , operative complication rates and component malposition rates .
However , the beneficial effect of MIS THA on functional recovery has to be proven .
The results also indicate that CAS THA , though result ing in an increase in operative time , may have a positive effect on operative blood loss and operative complication rates .
More importantly , the use of CAS results in better positioning of acetabular component of the prosthesis
Background Both minimally invasive surgery ( MIS ) and computer-assisted surgery ( CAS ) for total hip arthroplasty ( THA ) have gained popularity in recent years .
We conducted a qualitative and systematic review to assess the effectiveness of MIS , CAS and computer-assisted MIS for THA .