Medial Parapatellar Group Research Articles

Mid-vastus approach induces milder short-term effects on postural control compared to parapatellar approach in total knee arthroplasty.

BackgroundMid-Vastus and Medial Parapatellar techniques are used for total knee arthroplasty. Their short-term effects within the first month after surgery are yet unexplored. The purpose of this study was to compare Mid-Vastus and Medial Parapatellar effects on knee strength and balance control, at 5 days, 2 weeks and one month after surgery. It was hypothesized that Mid-Vastus would induce milder effects on the dependent variables due to its less invasive nature. MethodsTwenty females, randomly assigned to either the Mid-Vastus or the Medial Parapatellar group performed knee flexion-extension force and 30 s of bipedal stance before, 5 days, 2 weeks and one month after surgery. Maximum force, weight distribution and travel distance of the Center of Pressure were calculated. FindingsBoth groups showed decreased force output at all post-measurements compared to before surgery. Medial Parapatellar group showcased significantly higher travel distance at the 2 weeks measurement (Z = −2.268, p = .023, |r| = 0.507) compared to before surgery. This result was also imprinted on the travel distance of the non-surgical knee limb in the post (t = 3.259, p = .004, d = 1.456), 2 weeks (Z = −2.570, p = .009, |r| = 0.574) and one month measurement (t = 2.653, p = .016, d = 1.185). InterpretationWhile force is affected for both approaches, Mid-Vastus approach does not affect postural control. Therefore, Mid-Vastus is a less invasive technique compared to Medial Parapatellar. This work highlights the differences between Mid-Vastus and Medial Parapatellar approaches at least until the first month of rehabilitation.

Comparison of short-term radiographic outcomes of medial parapatellar, mini-midvastus, and subvastus surgical approaches in fast-track total knee arthroplasty

Purpose: Due to the difficulties in accessing the knee joint, correct prosthesis placement is of great importance during the implementation of total knee arthroplasty (TKA). This study aimed to compare short-term radiographic X-ray outcomes in patients who underwent fast-track TKA with medial parapatellar (MPP), mini-midvastus (mMV), or subvastus (SV) surgical approaches.
 Materials and methods: Between 2018 and 2020, 93 patients operated with MPP, mMV, and SV surgical approaches and who had complete data of radiographic outcomes before and sixth-week postoperative were retrospectively analyzed and patients divided into three groups: MPP (n=31), mMV (n=31), and SV (n=31). The alignments of preoperative and sixth-week postoperative X-ray images of the surgical approaches were measured. The operative time of fast-track TKA implementation with MPP, mMV, and SV surgical approaches was recorded.
 Results: The MPP group had higher preoperative lateral distal femoral angle than the mMV group and a higher preoperative lateral proximal femoral angle than SV group (p=0.018 and p=0.027, respectively). The mMV group had higher postoperative proximal medial tibial angle than SV group (p=0.011). In the postoperative sixth week, the MPP and mMV groups had a lower posterior tibial slope angle than SV group (p=0.001). The MPP approach had significantly shorter operative time than mMV and SV approaches (p=0.001).
 Conclusion: The outcomes indicate that MPP, mMV, and SV surgical approaches are preferable and feasible in obtaining a satisfactory prosthesis alignment during fast-track TKA. The MPP approach may be preferable because of its shorter operative time and potential advantage in minimizing surgical complication risks.

Midvastus Versus Medial Parapatellar Approach in Simultaneous Bilateral Total Knee Arthroplasty

BackgroundThe purpose of this study was to compare the postoperative outcomes over a period of 3 years in patients who underwent bilateral total knee arthroplasty (TKA) using midvastus (MV) versus medial parapatellar (MPP) approaches. MethodsIn this retrospective study, 2 propensity-matched cohorts of patients who underwent simultaneous bilateral TKA via MV (n = 100) and MPP (n = 100) approaches from January 2017 to December 2018 were compared. Surgical parameters compared were surgery time and the incidence of lateral retinacular release (LRR). Clinical parameters including the visual analog score for pain, time for straight leg raise (SLR), range of motion, the Knee Society Score, and the Feller patellar score were assessed in the early postoperative and follow-up periods up to 3 years. Radiographs were evaluated for alignment, patellar tilt, and displacement. ResultsLRR was performed on 17 knees (8.5%) in the MPP group and 4 knees (2%) in the MV group which was significant (P = .03). The time to SLR was significantly lower in the MV group. There was no statistically significant difference in the length of hospital stay between the groups. The visual analog score, range of motion, and Knee Society Score were better in the MV group within 1 month (P < .05), but no statistically significant differences were found later. Patellar scores, radiographic patellar tilt, and displacements were similar at all follow-up periods. ConclusionIn our study, the MV approach had faster SLR, less LRR, and better pain and function scores in the first few weeks after TKA. However, its effect on different patient outcomes has not been sustained at 1 month and further follow-up points. We recommend that surgeons use the surgical approach with which they are most familiar.

Comparison of subvastus and medial parapatellar approaches in primary total knee arthroplasty in term of clinical outcome

Background &amp; objectives: The purpose of this study was to determine differences in clinical outcome between subvastus and medial parapatellar approach in primary total knee arthroplasty. Methods: This is a prospective randomized study; we compared the clinical results of primary total knee arthroplasty using Subvastus and medial Parapatellar approaches in 34 patients. The standard medial Parapatellar approach used in 19 patients and Subvastus approach used in 15 patients. Clinical outcome assessed using knee society score, time to return quadriceps function and visual analogue scale for pain. Results: The mean follow-up time was 3 months. Pain improved significantly overtime in both groups. However, when comparing groups together, patients in subvastus group had better numerical visual analogue scale score at 3rd day postoperatively, nevertheless, no significant differences found at other follow up times (8.11, 6.05, 4.26, 2.32, 1.47 for medial parapatellar group and 8.20, 4.47, 4.0, 1.67, 1.07 for subvastus group at preoperative, 3rd day, 2, 6 and 12 weeks postoperative respectively for both groups). Subvastus group had earlier return of quadriceps function by 1.9 days which was significant statistically. Knee society score improved significantly overtime without any significant differences when comparing both groups together at any time of the follow up periods (, 66.42, 105.21, 137.63, 155.53 for medial parapatellar group and, 62.53, 107.53, 137.6, 155.81 for subvastus group at preoperative, 2, 6 and 12 weeks postoperative respectively for both groups). Conclusions: Subvastus approach allowed earlier return of quadriceps function and less pain in the early postoperative day. In term of physical and functional outcome, none of two surgical approaches showed advantage over the other

SMOC approach for total knee arthroplasty in valgus knees

ObjectiveThis study was performed to compare clinical outcomes among patients with valgus knees undergoing total knee arthroplasty via the medial parapatellar approach and the subvastus with minimal oblique cut approach.MethodsA total of 232 patients (246 knees) undergoing total knee arthroplasty between December 2014 and December 2016 were retrospectively included in the investigation. The study population consisted of 120 patients (128 knees; 32 men and 88 women) with a mean age of 62.43 ± 8.12 years treated via the medial parapatellar approach, and 112 patients (118 knees; 30 men and 82 women with a mean age of 63.15 ± 7.83 years) treated via the subvastus with minimal oblique cut approach. Nine preoperative parameters (number of patients, sex, age, body mass index, number of knees, valgus angle, visual analogue scale score, range of motion, Hospital for Special Surgery score), five perioperative parameters (operative time, amount of drainage, Visual analogue scale score at 24 h after the operation, time to straight leg raising, radiological alignment), and two postoperative parameters (range of motion, Hospital for Special Surgery score) were assessed at 1 day, 1 week, 6 weeks, 8 weeks and 1 year after the operation, along with postoperative complications.ResultsThere were no significant differences in the nine preoperative parameters between the two groups. The subvastus with minimal oblique cut group had a longer operative time, while the parapatellar approach group showed more drainage and a higher mean Visual analogue scale score. Compared to the medial parapatellar group, the subvastus with minimal oblique cut group had a shorter time to straight leg raising. There were no differences in radiological alignment between the two groups. The groups showed similar range of motion and Hospital for Special Surgery scores at 8 weeks and 1 year, but both were higher in the subvastus with minimal oblique cut group at 1 day, 1 week and 6 weeks. During postoperative follow-up, postoperative subluxation of the patella occurred in five cases in the medial parapatellar group. Neither group showed any instability, recurrent valgus deformity or radiographic loosening.ConclusionThe subvastus with minimal oblique cut approach provides excellent early recovery for total knee arthroplasty of valgus knees with no increase in complications.

Does the type of surgical approach affect the clinical outcome of total knee arthroplasty?

BackgroundThe aim of the study was to investigate the issue of medial midvastus (MMV) vs. medial parapatellar (MPP) approaches in total knee arthroplasty (TKA). It was hypothesized that the two surgical approaches would produce significantly different results with respect to patient-reported knee score outcome (hypothesis 1), short-term postoperative range of motion (ROM) (hypothesis 2), long-term postoperative ROM (hypothesis 3) and prosthesis survival (hypothesis 4).MethodsA retrospective comparative study design was applied. Data sets were obtained from the state arthroplasty registry. The Western Ontario and McMaster Universities osteoarthritis index (WOMAC) data were analyzed from preoperative and 1 year postoperatively. The ROM data were analyzed for the time points preoperative, postoperative days 4 and 10 and 1 year.ResultsAvailable were 627 cases (407 MMV vs. 220 MPP) and 1 year postoperatively there were no significant differences between groups regarding the WOMAC scores (hypothesis 1). Early postoperatively on days 4 and 10 after TKA there were no differences between groups (p = 0.305 and p = 0.383, respectively, hypothesis 2). Likewise, ROM did not significantly differ between the groups 1 year after TKA (p = 0.338, hypothesis 3). The 5‑year prosthesis survival did not differ between the groups and showed 94.46% (95% confidence interval, CI 90.69–96.73%) in the MMV group and 94.33% (95% CI 89.96–96.83%) in the MPP group (p = 0.664, hypothesis 4).ConclusionBoth surgical approaches produce equivalent clinical results in terms of early postoperative ROM, late postoperative ROM and 1‑year WOMAC. The same prosthesis survival rates can be expected.

Total diz artroplastisinde subvastus ve medial parapatellar yaklaşımın klinik ve radyolojik sonuçlarının değerlendirilmesi

Introduction: The aim of this study is to compare clinically and radiologically the subvatus (SV) and medial parapatellar (MPP) approaches performed in patients undergoing total knee arthroplasty (TKA) due to severe gonarthrosis. Materials and methods: Patients who underwent TKA between 2015 and 2019 were divided into two groups, SV and MPP, according to the type of approach performed. Demographic, clinical, and surgical information of the patients were evaluated. Knee Society Clinical Rating System (KSS) and visual analogue scale (VAS) scores were used for functional evaluation. AP and lateral orthoroentgenograms and knee radiographs taken at the last follow-up were used for radiological evaluation. Results: The mean duration of surgery and tourniquet was significantly higher in the SV group. (p &lt;.001 and p &lt;.001, respectively). Mean blood loss and number of blood transfusions were significantly higher in the MPP group. (p &lt;.001 and p &lt;.001, respectively). Opiate analgesic need, straight leg raising time and hospitalization time were also significantly higher in the MPP group. (p &lt;.001, p &lt;.001 and p &lt;.001, respectively). Although the KSS, VAS scores, and the range of motion at the first month were better in the SV group, there was no difference between the two groups at 6 and 12 months. Conclusion: According to this study, with the SV approach used for TKA, postoperative blood loss and the need for transfusion decreased, the duration of hospitalization was shortened, postoperative pain was less, and functional scores were better. The only disadvantage is the prolonged operation time

Mini-midvastus versus medial parapatellar approach in total knee arthroplasty: difference in patient-reported outcomes measured with the Forgotten Joint Score

BackgroundLow knee awareness after minimally invasive total knee arthroplasty (TKA) has become the ultimate target of a natural-feeling knee that meets patient expectations. The objective of this research was to compare the clinical outcomes of TKA via the mini-midvastus (MMV) approach or the medial parapatellar (MPP) approach, and to evaluate which approach can lead to a better quality of life after surgery.MethodsFrom January 2015 to December 2016, a retrospective cohort study was conducted in 330 patients who underwent TKA via a mini-midvastus (MMV) approach. During this period, we also selected 330 patients who underwent TKA via a medial parapatellar (MPP) approach (MPP group) for comparison. Clinical results were assessed with the visual analog scale score for pain, range of motion, and the Knee Society Score. The Forgotten Joint Score was used to analyze the ability to forget the joint.ResultsThere were significant differences with regard to visual analog scale score, range of motion, and the Knee Society Score until 6 months after surgery between the MMV and MPP groups (p < 0.05), but the differences were not significant at 12 months, 24 months, and 36 months after surgery. However, there were significant differences in the Forgotten Joint Score between the groups during the follow-up period (p < 0.05).ConclusionWhen forgetting the artificial joint after TKA is the ultimate target, better quality of life can be acquired by performing TKA via the MMV approach. In addition, compared with the MPP approach, the MMV approach can offer less pain and a faster recovery.

Effect of the surgical exposure on the early postoperative period after total knee arthroplasty

Total knee arthroplasty has become one of the most successful and safest surgical procedures in orthopedic surgery. Of the many different types of surgical exposure, the most common, so-called medial parapatellar (MP) incision is the cut of the quadriceps tendon, which impairs extensor function. In contrast, subvastus (S) exposure, which spares the extensor apparatus, may promise better healing. The purpose of our prospective observational study at the Orthopedic Clinic of Semmelweis University is to compare the effects of the MP and the S excision on the early postoperative period. The 60 patients enrolled were randomly assigned to two different groups according to the type of intervention. In the study, we measured the effects of the two different methods of surgical exposure on homogeneous patient groups in the early postoperative period based on international literature and the parameters we defined. Visual analog scale (VAS) measured resting and active pain levels for the first 10 days, suggesting a more pronounced difference in active VAS values for the S group. In the case of active VAS, patients in the S group also had significantly less pain on days 2, 3, and 10 than in the MP group. Taking into account the results of the other days, it is in favour of preserving the integrity of the extensor apparatus for improved postoperative functionality. Patients' knee joint range of motion was also measured. On day 1, those in the S group were significantly larger. As the days progress, MP group members catch up with S group during their rehabilitation. Group S patients had an average of 1.944 days to extended leg elevation, which is nearly two days shorter compared to the MP group (p<0.0001). After statistical analysis of data, subvastus exposure appears to be more beneficial in the rehabilitation of the early postoperative period. However, large-scale, multicentre observational studies are required to establish evidence. Orv Hetil. 2020; 161(29): 1208-1214.

Can the Surgical Approach to Total Knee Arthroplasty Influence Early Postoperative Outcomes? - A Comparative Study between Trivector and Medial Parapatellar Approaches.

Background:Trivector approach to total knee arthroplasty (TKA) is a quadriceps tendon sparing approach, whereas the medial parapatellar (MPP) approach involves making a longitudinal incision in quadriceps tendon. We postulated that quadriceps-sparing approach such as trivector should make postoperative rehabilitation easier and ultimately reduce the length of hospital stay.Objectives:The aim of the study is to compare the early postoperative outcomes of the TKA performed through the trivector and the MPP approaches.Methodology:We prospectively reviewed the results of 56 consecutive patients operated on by two knee surgeons: one routinely performs trivector and the other an MPP approach. Both the groups consisted of 28 patients each. We looked at operative times, the time taken to perform straight leg raise (SLR), range of movements achieved before discharge, and length of the hospital stay.Results:The mean time taken for performing the surgery through the MPP approach was 56 min, whereas, for the trivector approach, it was 54 min (P = 0.31). The mean time taken to perform SLR in the MPP approach group was 3.5 days, whereas in the trivector group, the meantime taken for SLR was 2.5 days (P = 0.003). The average extension at the time of discharge in the MPP group was 3.8°, and in the trivector group, it was 0.86° (P = 0.007). The average knee flexion at the time of discharge in the MPP group was 84.2°, whereas in the trivector group, it was 86.5° (P = 0.199). The average hospital stay in the MPP group was 5.96 days, whereas in the trivector group, it was 4.84 days (P = 0.11).Conclusions:The trivector approach patients took significantly less time to do SLR and achieved a better range of extension before discharge from the hospital. The patients with trivector approach were discharged early by one day, although it is not statistically significant, it is clinically significant.

Comparison of minimally invasive approaches and standard median parapatellar approach for total knee arthroplasty: A systematic review and network meta-analysis of randomized controlled trials.

Minimally invasive total knee arthroplasty (TKA) has been actively advertised by the orthopedic industry. The purpose of this network meta-analysis was to comprehensively compare the effectiveness of four minimally invasive surgery (MIS) approaches and the medial parapatellar (MPP) approach to improve the American Knee Society Score (KSS) in primary TKA. Studies were comprehensively searched on PubMed, Embase, Cochrane Library (CENTRAL), Web of Science and Science Direct up to June 2018 with a major focus on the outcome of KSS. Risk of bias was assessed using the Cochrane risk of bias tool. Quality assessment was performed using the GRADE system. Both pair-wise and network meta-analyses are calculated to comprehensively compare the effectiveness of four MIS and TKA approaches. Eleven trials with 1025 knees undergoing TKA were included. Our analysis showed that both MPP and MIS approaches provided improvement in terms of short-term (four-eight weeks) total, objective and functional KSS. The network-meta analysis revealed that MIS approaches showed a trend towards superior KSS improvement over standard MPP approaches. However, statistical advantages were only observed in the mini-MPP group for functional KSS compared to the conventional MPP and quadriceps-sparing (QS) groups. Evidence shows that MIS TKA approaches are effective alternatives to MPP approaches. However, orthopedic surgeons should be cautiously optimistic about minimally invasive TKA in terms of KSS improvement.

Mini-subvastus versus medial parapatellar approach for total knee arthroplasty: a prospective randomized controlled study.

Whether minimally invasive total knee arthroplasty (MIS-TKA) could offer better and faster recovery without the deviation of post-operative prosthesis position and limb alignment is still controversial. This prospective and randomized study was conducted to compare the clinical and radiological outcomes between patients who underwent the mini-subvastus approach of MIS-TKA and those who underwent the medial parapatellar approach of traditional TKA. Fifty patients, including 50 knees, who required TKA due to osteoarthritis were randomized to the mini-subvastus group (group I) or the medial parapatellar group (group II). All patients accepted the same method of anaesthesia, equal support therapy and identical rehabilitation exercise after surgery. The evaluation system included operation time, tourniquet time, blood loss, skin incision length in flexion, straight leg raising time, the time of lower limb muscle strength up to grade 4, the time of walking with aid or without aid, the time of walking up and down the stairs, the active flexion angle, range of movement (ROM), the Knee Society Scores (KSS), visual analogue score for pain (VAS), hospital stays and radiographic outcomes. The mini-subvastus approach offered smaller skin incision length in flexion, but at the cost of operation time (P < 0.001). No significant difference was found in tourniquet time and blood loss. The patients in group I could achieve straight leg raising, the lower limb muscle strength up to grade 4, walking with or without aid, and walking up and down the stairs earlier (P < 0.001). The active flexion angle, ROM, VAS and KSS in group I were superior to those in group II until six months post-operatively (P < 0.001), but the differences was not apparent at 12months post-operatively. More importantly, there was no significant difference between the two groups on radiological outcomes (P > 0.05). The mini-subvastus approach could offer faster recovery, less pain and shorter hospital stays without compromising the principles of proper prosthesis position and limb alignment compared with the medial parapatellar approach.

Approach to Total Knee Replacement: A Randomized Double Blind Study between Medial Parapatellar and Midvastus Approach in the Early Postoperative Period in Asian Population.

The purpose of this randomized study was to compare clinical and surgical outcomes of total knee replacements (TKRs) in the early postoperative period using midvastus approach versus medial parapatellar approach in Asian population in a double blind manner. Forty-two knees each were operated using midvastus approach and the medial parapatellar approach. Clinical parameters that were evaluated included Knee Society score (KSS); knee pain using visual analogue scale (VAS) on day 1, 1 week, and 1 month; time required to straight leg raise (SLR); patellar tracking; mean extensor lag at 1 week and 1 month; and time of discharge from the hospital. Surgical parameters that were evaluated included tourniquet time, incidence of lateral retinacular release, estimated blood loss, and any complications during the surgery. KSS at 1 week and 1 month postoperatively were significantly higher in the midvastus group as compared with medial parapatellar group; though similar at 3 months, 6 months, and 1 year. The patients in midvastus group required fewer number of lateral retinacular releases; achieved SLR earlier; had less mean extensor lag at 1 week; had less mean VAS score at day 1, 1 week, and 1 month; and had shorter hospital stay. There was no significant difference in the mean tourniquet time and estimated blood loss. One patient had patellar maltracking in the medial parapatellar group as compared with none in midvastus group. Midvastus approach to TKR results in quicker functional recovery with early discharge and rehabilitation in the Asian population as compared with medial parapatellar approach.

Quadriceps sparing (subvastus/midvastus) approach versus the conventional medial parapatellar approach in primary knee arthroplasty

IntroductionQuadriceps-sparing (subvastus/midvastus) approach has emerged as an alternative to the classical medial parapatellar approach in total knee arthroplasty with the results claiming faster rehabilitation in the quadriceps sparing group. The present study was conducted to determine if the quadriceps sparing (subvastus/midvastus) approach offers any advantages over the classical medial parapatellar approach in primary knee replacements. Material and methods55 patients undergoing unilateral TKA were randomized into two groups: the subvastus/midvastus group and the medial parapatellar group. The patients were assessed preoperatively and postoperatively at 7 days, 1 month, 3 months and finally at 6 months. Knee Society Scoring was used to compare the groups. Perioperative blood loss, duration of surgery and need for lateral release were also compared. The patient was kept on same pain management and postoperative rehabilitation protocol. Statistical analyses tested the null hypotheses of no differences in patients treated with either group at 95% significance level (p<0.05). ResultsThe difference between the two groups in terms of duration of surgery and perioperative blood loss were statistically not significant. Lateral release was required in 13.8% of patients in the parapatellar group compared to 3.8% of patients in the quadriceps-sparing group. On comparing the postoperative Knee Society Scores of the two groups at each follow up the difference was statistically significant at 7 days and 4 weeks postoperatively (p value<0.05) but the difference between the two groups at 3 and 6 months was not significant statistically (p value>0.05). ConclusionQuadriceps sparing approach (subvastus/midvastus) offers advantages over the standard medial parapatellar approach in terms of better pain relief and faster rehabilitation in the early postoperative period.

Outcome of subvastus approach in elderly nonobese patients undergoing bilateral simultaneous total knee arthroplasty: A randomized controlled study

Background:Subvastus approach in total knee arthroplasty (TKA) spares the quadriceps and may assist in faster rehabilitation. The present randomised controlled study was conducted to determine if the subvastus approach results in early recovery, faster mobilization, shorter hospital stay, and improved function.Materials and Methods:100 patients undergoing simultaneous bilateral TKA were randomized into two groups: subvastus group and medial parapatellar group. The patients were assessed clinically using VAS, time to straight leg raise, ability to stand with walker, ability to use a commode chair, ability to climb stairs, flexion at discharge, and day of discharge. Perioperative blood loss and duration of surgery were also compared. The patient were kept on same pain management and physiotherapy protocol. The evaluation was done at day 0,1,3 and at discharge. Statistical analyses tested the null hypotheses of no differences in patients treated with either group at 95% significance level (P < 0.05).Results:The VAS score was significantly lower in subvastus group on day 1 and day 3. Also mean hospital stay was 2.04 days less in subvastus group. Patients with subvastus approach were able to perform straight leg raising 0.44 days earlier. Though time to stand with walker was same for both groups, the ability to use commode chair, and climb stairs was significantly early (P < 0.05) in the subvastus group. The average flexion at the time of discharge in subvastus and parapatellar group were 100.8 and 96.8°, respectively. The mean perioperative blood loss in subvastus group and parapatellar group were 343 ml and 372 ml, respectively. Average surgical time required for subvastus approach and parapatellar approach were 108.5 and 94.3 min, respectively.Conclusions:Subvastus approach produce appreciably less pain and faster mobilization due to lesser insult to quadriceps, thus assisting in early rehabilitation, shorter hospital stay, less expenditure, and more patient satisfaction.

Patellar Tracking and Anterior Knee Pain are Similar After Medial Parapatellar and Midvastus Approaches in Minimally Invasive TKA

Since the medial parapatellar (MPP) approach in conventional TKA can cause patellar maltracking and anterior knee pain, some orthopaedic surgeons use the midvastus (MV) approach instead of the MPP approach to reduce patellar maltracking. Minimally invasive surgical (MIS) TKA has been developed to limit the damage to the surrounding muscle and reduce the necessity of patellar eversion during surgery. Thus, MIS TKA might be associated with proper patellar tracking and a low incidence of anterior knee pain. However, this presumption has not been confirmed. We asked whether the incidence of patellar maltracking and anterior knee pain differed with the MV and MPP in association with MIS TKA. We prospectively followed 59 patients (60 knees) treated with 60 primary cemented MIS TKAs from August 2009 to September 2010. We randomized the patients into two groups: 30 who had a limited MPP approach and 30 who had a mini-MV approach. We recorded the occurrence of anterior knee pain, patellar tilting, and subluxation. The minimum followup was 12 months (mean, 18.03 months; range, 12.00-25.08 months). We found no differences in anterior knee pain (two of 30, 7% versus two of 30, 7%), mean patellar tilt (3.4º ± 2.9º versus 3.0 ± 2.3º), and mean patellar subluxation (1.5 ± 1.1 mm versus 1.1 ± 0.7 mm) between the limited MPP and mini-MV groups, respectively. MIS TKA using either the MPP or MV approach has a low incidence of patellar maltracking and anterior knee pain.

Paper 98: Sub-vastus Approach Versus the Medial Parapatellar Approach in Primary Total Knee: A Controlled Trial

Orthopaedic surgeons vary in their surgical approaches to total knee arthroplasty. The aim of this investigation was to compare outcomes after two different surgical approaches. The study was a prospective single-centre longitudinal randomized controlled trial. A sub-vastus approach was compared with a medial para-patellar approach. Participating surgeons elected to randomize their patients to one of the two types of approach. Outcomes included the Knee Society (KS) Clinical Rating System, WOMAC Osteoarthritis Index, SF-36, and EuroQol (measured at 1, 6, 12 and 52 weeks post-operatively compared to baseline) complications, surgeon rated ease of exposure, and proportion of patients who had a lateral release. Two hundred and thirty one patients were randomized to the two approaches. One hundred and sixteen patients were randomized to the sub-vastus approach. At one week compared to baseline, range of motion, KS global, KS knee, and KS pain scores were significantly better in the sub-vastus group. At six weeks, the medial para-patellar group tended to have better outcomes, but not statistically significantly. At fifty-two weeks compared to baseline, the WOMAC global and pain scores, the SF36 physical function and role-physical scores, and the EuroQol utility and pain score were significantly better in the sub-vastus group. Surgeons reported the ease of exposure in the sub-vastus group was significantly worse on average. This trial is the largest of its kind to date, and the first, so far as we are aware, to compare clinical outcomes of different surgical approaches at one year post-operatively. The sub-vastus approach to total knee arthroplasty was more effective than a medial para-patellar approach at both one week and fifty-two weeks post-operatively in patients whose surgeons considered either approach would be suitable. However, surgeons reported worse ease of exposure in the sub-vastus group.

A prospective randomised study of minimally invasive midvastus total knee arthroplasty compared with standard total knee arthroplasty

IntroductionProposed advantages of minimally invasive surgery include shorter hospital stay, less blood loss, and a greater range of motion but potential concerns are raised about both prolonged learning curves and a compromise in exposure leading to implant malposition. Patients and methodsThis powered study evaluates the outcomes of 80 patients randomised to have mini-midvastus (MMV) approach or standard medial parapatellar (MPP) approach. Rehabilitation protocols and discharge criteria were standardised. Patients were discharged home directly, capable of safe independent care. Validated outcome measures were recorded post-operatively at intervals up to 1year. Independent, blinded review of post-operative x-rays was obtained. ResultsLength of stay was similar in the MMV and MPP groups (median 3.73days vs. 3.75days). No statistically significant differences were detected in either the demographic data or any intra-operative variable apart from blood loss and incision length. No statistically significant difference in clinical outcome measures (Oxford/Knee Society Scores) or radiographic analysis was observed. ConclusionThe MMV approach does not appear to confer any clinically significant benefit apart from a smaller surgical scar, compared to the MPP surgical technique.Level of evidence I: randomised control trial.R.E.C. 040301.

Subvastus and Medial Parapatellar Approaches in TKA: Comparison of Functional Results

The purpose of this study was to compare the clinical results of total knee arthroplasty (TKA) in the early and late postoperative period using subvastus and medial parapatellar approach. A prospective randomized controlled study was conducted in a group of 169 patients (180 TKAs) with 2-year follow-up. Patients were divided into a study group (97 TKAs) with a subvastus approach and a control group (83 TKAs) with a parapatellar approach. Assessment of the results of both operating approaches was based on functional, clinical Knee Society Score, and pain (visual analog scale). Patients in the subvastus group achieved full active extension, better range of motion, and better Knee Society Score results at 12 days, 6 weeks, and 12 weeks earlier than patients in the medial parapatellar group. They also had less pain at 12 days. No statistically significant differences existed between assessed end points in both groups at 24- and 52-weeks, and 24-months postoperatively. The subvastus approach has given patients better early clinical results; however, at longer follow-up, both groups had similar outcomes. The potential benefits of the subvastus approach are: protection of the extensor mechanism from damage, less risk of damaging the blood supply to the patella, earlier clinical recovery, and less pain in the early postoperative period. The subvastus approach is an alternative to the standard medial parapatellar approach in TKA. It can be used with equally good results, especially taking into consideration positive clinical aspects in the early postoperative period.

Total Diz Artroplastisinde Midvastus Yaklaşımına Karşılık Medial Parapatellar Yaklaşım: Erken Fonksiyonel Sonuçların Karşılaştırılması

Objective: The purpose of this study was to compare the early outcomes of total knee arthroplasty (TKA) using midvastus (MV) versus medial parapatellar (MPP) approaches on both knees. Material and Methods: Fifty two consecutive patients (104 knees) who underwent single-stage bilateral TKA performed by two surgeons between August 2004 and December 2007 were evaluated retrospectively at a minimum follow-up duration of two years. Patients were divided into two groups. In the MV group, consisted of 27 patients, a midvastus approach was performed on both knees. Besides, in the MPP group, consisted of 25 patients, a medial parapatellar approach was performed on both knees. Results: Mean follow-up duration was 40.2 months (27-66 months) and 42.3 months (25-61 months) for the MV and MPP groups, respectively. The Knee Society Clinical Rating System (knee and function score), the range of motion, patellofemoral pain questionnaire, patient satisfaction questionnaire and radiography were used for the evaluation of both groups. Lateral retinacular release (LRR) was performed on four knees in the MPP group whereas it was not used in the MV group. There was a significant difference between the two groups with regard to the rate of LRR (p= 0.034). Axial radiographs revealed that six patellas in the MPP group, but only one in the MV group exhibited lateral displacement postoperatively (p= 0.039). Conclusion: The preservation of normal patellar tracking is important for TKA. In this study, the midvastus approach required significantly less LRR as compared to the medial parapatellar approach.