J Knee Surg 2017; 30(08): 793-797
DOI: 10.1055/s-0036-1597978
Original Article
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

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

Mohammed Ammar Aslam
1   Department of Orthopaedics, Maulana Azad Medical College and Associated Lok Nayak Hospital, New Delhi, India
,
Aamir Bin Sabir
2   Department of Orthopaedic Surgery, Jawaharlal Nehru Medical College, Aligarh Muslim University, Aligarh, Uttar Pradesh, India
,
Vivek Tiwari
1   Department of Orthopaedics, Maulana Azad Medical College and Associated Lok Nayak Hospital, New Delhi, India
,
Sohail Abbas
1   Department of Orthopaedics, Maulana Azad Medical College and Associated Lok Nayak Hospital, New Delhi, India
,
Anurag Tiwari
1   Department of Orthopaedics, Maulana Azad Medical College and Associated Lok Nayak Hospital, New Delhi, India
,
Pritish Singh
1   Department of Orthopaedics, Maulana Azad Medical College and Associated Lok Nayak Hospital, New Delhi, India
› Author Affiliations
Further Information

Address for correspondence

Vivek Tiwari, MBBS, MS Orthopaedics
DNB Orthopaedics, Mir Dard Lane, Maulana Azad Medical College & Associated Lok Nayak Hospital
New Delhi 110002
India   

Publication History

16 January 2016

06 December 2016

Publication Date:
13 January 2017 (online)

 

Abstract

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.


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Total knee replacements (TKRs) have become one of the most commonly performed and most successful surgeries to relieve knee pain in osteoarthritic knees.[1] Various modifications are being sought to further improve the results and the long-term outcomes of the procedure and decrease the hospital stay and bed occupancy by such patients. Some of the areas where improvements are being contemplated include implant design,[2] patient selection, and the surgical approach used for arthrotomy. Among all these factors, the surgical approach can be easily modified by the surgeon.

The classic medial parapatellar approach has been postulated as the time-tested, safe, reproducible, and most commonly used approach for TKR.[3] This involves an intratendinous sagittal incision in the quadriceps tendon proximal to its insertion into the patella in its medial third.[3] The disruption of the quadriceps tendon has been said to affect the extensor function adversely, resulting in inferior functional outcomes and delayed recovery.[4] [5] Therefore, other alternative approaches were searched, which avoided damage to the extensor mechanism of the knee. In the early 1990s, midvastus approach became popular as the quadriceps sparing approach, which avoided disruption of the extensor mechanism. It involves detaching the vastus medialis fibers that attach distal to the patella from the patella, then splitting the muscle in its full thickness, parallel with these fibers, from the superior pole of the patella down to their origin on the femur by blunt dissection.[6] The reported benefits of this approach included shorter hospital stay, decreased blood loss, quick functional recovery, reduced postoperative pain, and decreased patellar complications.[6]

Various studies have compared the functional and clinical outcomes of the medial parapatellar and the midvastus approach with TKR; however, there is no definite conclusion as yet regarding the superiority of one approach to the other.[7] [8] [9] Moreover, only few of them were prospective randomized double blinded studies, and still less were related to Asian population. The aim of the present randomized study was to evaluate the clinical outcomes of TKR performed by the midvastus approach and compare results with those performed by the medial parapatellar approach in Asian population in a double blind manner.

Materials and Methods

Between April 2010 and April 2012, patients presenting to our outpatient department with severe knee osteoarthritis (Kellgren-Lawrence grades 3 and 4) and willing for TKR were included in the study. The exclusion criteria included body mass index (BMI) > 40, fixed varus deformity > 30 degrees, fixed valgus deformity > 30 degrees, fixed flexion deformity > 30 degrees, severe visual impairment, inflammatory arthritis, active infection, comorbid conditions such as psychiatric illness, neuromuscular disorders, patients not motivated for physiotherapy, or not ready to undergo lifestyle modifications required after arthroplasty. The study was approved by the Institutional Ethics Committee. Written informed consent was obtained from all the patients before recruitment into the study.

A total 60 patients (84 knees) were enrolled in our prospective randomized study. Forty-two knees were randomly assigned to group I (medial parapatellar approach) and 42 knees were assigned to group II (midvastus approach) using computer-generated random numbers. Demographic data were collected preoperatively from all the patients and recorded on a prefixed proforma. Assessment of the clinical outcome was done for all knees preoperatively, at 1 week, 1 month, 3 months, 6 months, and 1 year. Each knee was evaluated using Knee Society scoring (KSS) system.[10] Evaluation of knee pain was done on day 1, 1 week, and 1 month by a 10-point visual analogue scale (VAS), with 10 points indicating worst pain and 0 point indicating no pain. All the knees were operated by the same surgeon. The implant used in each case was a posterior stabilized, fixed bearing, cemented design (Scorpio NRG, Stryker Co., Kalamazoo, MI). Patella resurfacing was not done in any patient. Surgical parameters that were evaluated included tourniquet time, incidence of lateral retinacular release, estimated blood loss, and any complications during the surgery.

Surgical Technique

All TKR were performed using the medial parapatellar approach in group I and midvastus approach in group II. All the surgeries were done under combined spinal epidural anesthesia. After painting and draping the knee, surgical approach was decided using random numbers. The length of the skin incision was constant, 15 cm in all the cases so that patients as well as the assessor were blind as to the approach used. A longitudinal midline skin incision was used in each case. In group I, sagittal incision was given in the quadriceps tendon at the junction of the medial third and lateral two-thirds; proximal to its insertion into the patella. In group II, the fibers of the vastus medialis were split to the full thickness of the muscle by blunt dissection, without disruption of the quadriceps tendon. The tibial surface was prepared first followed by femoral surface with the help of an extramedullary jig for tibia and an intramedullary jig for the femur. The patellar osteophytes were removed and the articular surface of the patella was smoothened with a rasp to make it congruent with the groove over the femoral component; patellar resurfacing was not done. After a thorough joint lavage with saline, the closure was done over a suction drain.

Patient-controlled analgesia was used during the first postoperative day in both the groups. The postoperative physiotherapy regimen was similar in the two groups, involving incremental increases in the degree of flexion in the postoperative period. Patients were discharged once they achieved stair climbing and 90 degrees of flexion. Assessments were done regarding time required to straight leg raise (SLR), patellar tracking, incidence of infection, mean extensor lag at 1 week and 1 month, and time of discharge from the hospital.

Statistical analysis was done using SPSS 10.0 (SPSS Inc., Chicago, IL). The analysis for continuous variables was done using the student's t-test. Chi-square test was used for the analysis of dichotomous variables. Statistical significance was said to be obtained when p value was < 0.05.


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Results

The patient's preoperative demographic characteristics (age, weight, height, BMI) were similar in the two groups ([Table 1]). In the surgical parameters, lateral retinacular releases were required in five patients in group I as compared with none in group II. The difference in the number of patients requiring lateral retinacular releases was found to be statistically significant on applying Fisher's exact test (p < 0.05). Although the mean drain output in group I (166 mL) was more than that in group II (157 mL), the difference was not statistically significant (p > 0.05). There was no significant difference among the other surgical parameters. The mean tourniquet time was 86 minutes in group I as compared with 80 minutes in group II (p > 0.05). There was no intraoperative complication seen in any of the patients in either group ([Table 2]).

Table 1

Preoperative demographic characteristics

Groups

Group I

Group II

No. of cases

42 (30 patients)

42 (30 patients)

Male:Female

6:24

14:6

Mean age (y)

68.6

68.8

Mean weight (kg)

74.1

74.3

Mean height (cm)

157.2

156.4

Mean BMI (kg/m2)

30.1

30.6

Abbreviation: BMI, body mass index.


Table 2

Comparison of surgical parameters between the two groups

Groups

Group I

Group II

Tourniquet time (min)

86

80

Blood loss (drain output) (mL)

166

157

No. of lateral releases

5

0

Complications

Nil

Nil

The mean preoperative KSS (knee and function) were similar in the two groups: 31.53 and 3.66 in group I and 31.04 and 3.4 in group II, respectively (p = 0.79). KSS was evaluated at 1 week, 1 month, 3 months, 6 months, and 1 year. The minimum follow-up was 1 year in both the groups (mean: 18 months, range: 12–24 months). There was no loss to follow-up. KSS at 1 week and 1 month postoperatively were significantly higher in group II as compared with group I (p < 0.001). However, the difference in the scores gradually became insignificant at 3 months follow-up (p = 0.71), which remained so at 6 months and 1 year ([Tables 3], [4]). The mean VAS score at day 1 was significantly less in group II (4.5) as compared with group I (6.1) (p < 0.05), and the difference was significant (p < 0.05) even at 1 week and 1 month (2.2, 3.8, and 1.5, 2.9; respectively). The mean amount of narcotic medication utilization on day 1 was also significantly less in group II as compared with group I (p < 0.05).

Table 3

Knee Society score (knee scores)

Groups

Group I

Group II

Preoperative score

31.53

31.04

1 wk

61.13

68.72

1 mo

82.4

87.28

3 mo

96.46

96.72

6 mo

97.33

97.35

1 y

98.37

98.19

Table 4

Knee Society score (function scores)

Groups

Group I

Group II

Preoperative score

3.66

3.4

1 wk

12

18.8

1 mo

61

66

3 mo

88

89

6 mo

96.65

97.2

1 y

98.4

98.6

The patients achieved SLR earlier in the midvastus group as compared with those of medial parapatellar group. The mean time to achieve SLR was 2.02 days in group II as compared with 3.42 days in group I, which was statistically significant (p < 0.001). Mean extension lag at 1 week was significantly less in the midvastus group (5.22 degrees) as compared with the medial parapatellar group (10.02 degrees) (p < 0.01). On the other hand, although the mean extensor lag at 1 month was less in the midvastus group, the difference was not found to be statistically significant (p > 0.05). There was significant difference in the average time of discharge from the hospital between the two groups; it was 8 days after surgery in group I as compared with 6 days in group II (p < 0.05) ([Table 5]). One patient of the medial parapatellar group developed patellar-maltracking postoperatively as compared with none in the other group. Three patients each of midvastus and medial parapatellar group developed pain over the proximal thigh postoperatively attributed to tourniquet application. Three patients of midvastus group and one patient of medial parapatellar group developed superficial skin necrosis and infection, which healed subsequently by daily cleaning and dressing. None developed deep infection.

Table 5

Functional comparison between the two groups

Groups

Group I

Group II

Median day to straight leg raise (SLR)

3.42

2.02

Mean extensor lag at 1 wk (degrees)

10.02

5.22

Mean extensor lag at 1 mo (degrees)

4.1

3.31

Days before discharge

8

6


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Discussion

TKR aims to achieve a painless, stable, and functional joint, and the results are closely dependent on the surgical technique used. During the last few decades, the surgery has become highly successful, reproducible, and durable. With the advancement of the surgical techniques and implant designs, the approach for the surgery is also evolving. It requires complete exposure of the knee joint and the articulating surfaces of the femur, tibia, and patella, for precise instrumentation.

Medial parapatellar arthrotomy is generally considered the standard surgical approach in TKR; however, concerns were raised regarding the disruption of extensor function due to its intratendinous incision and the incidences of abnormal patellar tracking with the approach, which in turn can cause severe complications including patellar dislocation or subluxation, fracture of patella, osteonecrosis, and component erosion.[11] To deal with the above concerns, subvastus approach was proposed, which resulted in better patellar tracking and preservation of the quadriceps mechanism.[12] However, it had its own share of problems, including difficult exposure, increased chances of postoperative hematoma, muscle ischemia, and apprehension with detachment of patellar tendon from its insertion.[13]

The midvastus or vastus-splitting approach was then introduced as a compromise between the earlier two approaches, representing an effort to maintain the benefits of the medial parapatellar as well as the subvastus approach and preserving the integrity of the extensor mechanism and patellar blood supply without compromising exposure.[6] Since then, there have been many studies comparing the different approaches for TKR; however, there is paucity of literature comparing the functional and clinical outcomes of medial parapatellar and midvastus approach in Asian population. Therefore, the aim of our prospective randomized study was to detect differences in functional, clinical, and surgical parameters in Asian patients undergoing TKR with medial parapatellar and midvastus approach, in a double blind manner.

In this study, preoperative KSS (knee and function) were recorded and analyzed; the mean preoperative KSS were similar in midvastus and medial parapatellar groups. The postoperative KSS at 1 week and 1 month were significantly higher in the midvastus group as compared with the medial parapatellar group. However, the difference in KSS gradually became insignificant at 3-month follow-up. With these findings, we infer that the midvastus arthrotomy provided definite functional advantage in the early postoperative period; however, the long-term outcomes were similar to that of medial parapatellar group. Some of the previous studies also concluded that midvastus approach resulted in better short-term functional outcome.[8] [14] [15] [16] On the other hand, other studies did not find any difference in the early functional scores between the two groups,[17] [18] [19] [20] though only few of them were double blind randomized trials.

On comparing the midvastus and the medial parapatellar groups, we found that the patients achieved SLR significantly earlier in the midvastus group as compared with those of medial parapatellar group. This finding was in accordance with similar previous studies.[15] [16] [17] [18] [20] [21] Keating et al, however, did not find earlier SLR with the midvastus approach.[19] Mean extensor lag at 1 week was also found to be significantly less with midvastus approach in comparison with the parapatellar approach in our study, although no significant difference was found at 1 month.

In our study, there was no requirement of lateral retinacular release in the midvastus approach group as compared with five times in the medial parapatellar group demonstrating significantly increased risk of patellar maltracking in the latter. Although Keating et al did not find any difference in the incidence of lateral release with the midvastus approach,[19] most of the recent studies demonstrated significantly less amount of lateral releases with this approach.[5] [8] [16] [17] [21] [22] Moreover, Ozkoc at al concluded that midvastus approach is better than medial parapatellar approach about late patellar tracking.[11]

In our study, we found significantly less postoperative pain in the midvastus group (as measured by the VAS score) on day 1, and this difference was maintained even at 1 week and 1 month. Most of the studies found that midvastus approach is associated with significantly less postoperative pain in the immediate postoperative period,[8] [14] [16] [21] [23] [24] whereas few studies did not find any significant difference between the two groups with this aspect.[17] [20] Most of the aforementioned studies evaluated postoperative pain within first week, however, and very few checked it at 1 month duration.

We found that the patients of the midvastus group were discharged from the hospital significantly earlier than those in the medial parapatellar group. This aspect has been very rarely compared between the two groups and never in Asian population. Mukherjee et al concluded that although the midvastus approach resulted in earlier SLR, it did not result in a shorter hospital stay in the British population.[15] Contrary to the aforementioned finding, Maru et al concluded that midvastus approach resulted in a significantly shorter hospital stay than the medial parapatellar approach in the British population.[20]

In our study, there was no statistically significant difference between the two groups regarding surgical time (equivalent to tourniquet time) and amount of blood loss, although midvastus approach resulted in less blood loss and reduced tourniquet time. Because these two factors have been described as indirect markers of exposure difficulty,[16] we conclude that, in contrast to the popular belief, midvastus approach does not pose significant difficulty in exposure for primary TKR. Song et al and White et al also had similar findings regarding the above parameters.[17] [21] Kelly et al and Fu et al found significantly less blood loss with the midvastus approach as compared with the medial parapatellar approach, although tourniquet and surgical times were found to be similar, respectively.[5] [16] In a meta-analysis, Liu et al found that midvastus approach was associated with longer operative time in comparison with the medial parapatellar approach.[14]

The main drawback to our study was a small sample size and a relatively shorter follow-up. Moreover, we did not look for kinematics of the knee in the two groups. Also, the study did not focus on the success of appropriate component placement using the two approaches, although there is a concern that approaches that decrease the visibility of the joint during TKR may be associated with a higher rate of component malalignment—particularly tibial malrotation. In the future, a comprehensive prospective study with longer follow-up would be necessary.


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Conclusion

The study showed that TKR performed with midvastus approach in the Asian population resulted in better functional outcome in the immediate postoperative period with decreased pain, thereby reducing the hospital stay. It also required significantly less lateral retinacular release without causing difficulty in exposure. The time required to achieve SLR was also significantly less with reduced early mean extension lag resulting in rapid rehabilitation. There was no significant difference in the surgery time and amount of blood loss. We conclude from our study that midvastus approach is a compatible, patient-, and surgeon-friendly approach for modern-era primary TKR.


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No conflict of interest has been declared by the author(s).

  • References

  • 1 Kurtz S, Mowat F, Ong K, Chan N, Lau E, Halpern M. Prevalence of primary and revision total hip and knee arthroplasty in the United States from 1990 through 2002. J Bone Joint Surg Am 2005; 87 (07) 1487-1497
  • 2 Hamilton WG, Sritulanondha S, Engh Jr CA. Results of prospective, randomized clinical trials comparing standard and high-flexion posterior-stabilized TKA: a focused review. Orthopedics 2011; 34 (09) e500-e503
  • 3 Insall J. A midline approach to the knee. J Bone Joint Surg Am 1971; 53 (08) 1584-1586
  • 4 Parentis MA, Rumi MN, Deol GS, Kothari M, Parrish WM, Pellegrini Jr VD. A comparison of the vastus splitting and median parapatellar approaches in total knee arthroplasty. Clin Orthop Relat Res 1999; (367) 107-116
  • 5 Kelly MJ, Rumi MN, Kothari M. , et al. Comparison of the vastus-splitting and median parapatellar approaches for primary total knee arthroplasty: a prospective, randomized study. J Bone Joint Surg Am 2006; 88 (04) 715-720
  • 6 Engh GA, Holt BT, Parks NL. A midvastus muscle-splitting approach for total knee arthroplasty. J Arthroplasty 1997; 12 (03) 322-331
  • 7 Liu Z, Yang H. Comparison of the minimally invasive and standard medial parapatellar approaches for total knee arthroplasty: systematic review and meta-analysis. J Int Med Res 2011; 39 (05) 1607-1617
  • 8 Alcelik I, Sukeik M, Pollock R, Misra A, Naguib A, Haddad FS. Comparing the mid-vastus and medial parapatellar approaches in total knee arthroplasty: a meta-analysis of short term outcomes. Knee 2012; 19 (04) 229-236
  • 9 Costa CR, Johnson AJ, Harwin SF, Mont MA, Bonutti PM. Critical review of minimally invasive approaches in knee arthroplasty. J Knee Surg 2013; 26 (01) 41-50
  • 10 Ewald FC. The Knee Society total knee arthroplasty roentgenographic evaluation and scoring system. Clin Orthop Relat Res 1989; (248) 9-12
  • 11 Ozkoc G, Hersekli MA, Akpinar S. , et al. Time dependent changes in patellar tracking with medial parapatellar and midvastus approaches. Knee Surg Sports Traumatol Arthrosc 2005; 13 (08) 654-657
  • 12 Hofmann AA, Plaster RL, Murdock LE. Subvastus (Southern) approach for primary total knee arthroplasty. Clin Orthop Relat Res 1991; (269) 70-77
  • 13 Fauré BT, Benjamin JB, Lindsey B, Volz RG, Schutte D. Comparison of the subvastus and paramedian surgical approaches in bilateral knee arthroplasty. J Arthroplasty 1993; 8 (05) 511-516
  • 14 Liu HW, Gu WD, Xu NW, Sun JY. Surgical approaches in total knee arthroplasty: a meta-analysis comparing the midvastus and subvastus to the medial peripatellar approach. J Arthroplasty 2014; 29 (12) 2298-2304
  • 15 Mukherjee P, Press J, Hockings M. Mid-vastus vs medial para-patellar approach in total knee replacement—time to discharge. Iowa Orthop J 2009; 29: 19-22
  • 16 Fu Pei-liang, Li Xiao-hua, Wu Yu-li, Xie Qing-yun, Sun Jiu-yi, Wu Hai-shan. Comparison of midvastus and standard medial parapatellar approaches in total knee arthroplasty. J Clin Rehab Tissue Eng Res 2008; 9: 1793-1796
  • 17 Song MH, Kim BH, Ahn SJ, Yoo SH, Lee MS. Comparison of midvastus and medial parapatellar approach for total knee arthroplasty. J Korean Orthop Assoc 2005; 40 (07) 902-907
  • 18 Nutton RW, Wade FA, Coutts FJ, van der Linden ML. Short term recovery of function following total knee arthroplasty: a randomised study of the medial parapatellar and midvastus approaches. Arthritis (Egypt) 2014; 2014: 173857
  • 19 Keating EM, Faris PM, Meding JB, Ritter MA. Comparison of the midvastus muscle-splitting approach with the median parapatellar approach in total knee arthroplasty. J Arthroplasty 1999; 14 (01) 29-32
  • 20 Maru M, Akra G, McMurtry I, Port A. A prospective comparative study of the midvastus and medial parapatellar approaches for total knee arthroplasty in the early postoperative period. Eur J Orthop Surg Traumatol 2009; 19 (07) 473-476
  • 21 White Jr RE, Allman JK, Trauger JA, Dales BH. Clinical comparison of the midvastus and medial parapatellar surgical approaches. Clin Orthop Relat Res 1999; (367) 117-122
  • 22 Altay MA, Erturk C, Akmese R, Isikan UE. Midvastus versus medial parapatellar approach in total knee arthroplasty: a comparison of early functional result. Turkiye Klinikleri J Med Sci 2011; 31 (05) 1106-1112
  • 23 Dalury DF, Jiranek WA. A comparison of the midvastus and paramedian approaches for total knee arthroplasty. J Arthroplasty 1999; 14 (01) 33-37
  • 24 Bäthis H, Perlick L, Blum C, Lüring C, Perlick C, Grifka J. Midvastus approach in total knee arthroplasty: a randomized, double-blinded study on early rehabilitation. Knee Surg Sports Traumatol Arthrosc 2005; 13 (07) 545-550

Address for correspondence

Vivek Tiwari, MBBS, MS Orthopaedics
DNB Orthopaedics, Mir Dard Lane, Maulana Azad Medical College & Associated Lok Nayak Hospital
New Delhi 110002
India   

  • References

  • 1 Kurtz S, Mowat F, Ong K, Chan N, Lau E, Halpern M. Prevalence of primary and revision total hip and knee arthroplasty in the United States from 1990 through 2002. J Bone Joint Surg Am 2005; 87 (07) 1487-1497
  • 2 Hamilton WG, Sritulanondha S, Engh Jr CA. Results of prospective, randomized clinical trials comparing standard and high-flexion posterior-stabilized TKA: a focused review. Orthopedics 2011; 34 (09) e500-e503
  • 3 Insall J. A midline approach to the knee. J Bone Joint Surg Am 1971; 53 (08) 1584-1586
  • 4 Parentis MA, Rumi MN, Deol GS, Kothari M, Parrish WM, Pellegrini Jr VD. A comparison of the vastus splitting and median parapatellar approaches in total knee arthroplasty. Clin Orthop Relat Res 1999; (367) 107-116
  • 5 Kelly MJ, Rumi MN, Kothari M. , et al. Comparison of the vastus-splitting and median parapatellar approaches for primary total knee arthroplasty: a prospective, randomized study. J Bone Joint Surg Am 2006; 88 (04) 715-720
  • 6 Engh GA, Holt BT, Parks NL. A midvastus muscle-splitting approach for total knee arthroplasty. J Arthroplasty 1997; 12 (03) 322-331
  • 7 Liu Z, Yang H. Comparison of the minimally invasive and standard medial parapatellar approaches for total knee arthroplasty: systematic review and meta-analysis. J Int Med Res 2011; 39 (05) 1607-1617
  • 8 Alcelik I, Sukeik M, Pollock R, Misra A, Naguib A, Haddad FS. Comparing the mid-vastus and medial parapatellar approaches in total knee arthroplasty: a meta-analysis of short term outcomes. Knee 2012; 19 (04) 229-236
  • 9 Costa CR, Johnson AJ, Harwin SF, Mont MA, Bonutti PM. Critical review of minimally invasive approaches in knee arthroplasty. J Knee Surg 2013; 26 (01) 41-50
  • 10 Ewald FC. The Knee Society total knee arthroplasty roentgenographic evaluation and scoring system. Clin Orthop Relat Res 1989; (248) 9-12
  • 11 Ozkoc G, Hersekli MA, Akpinar S. , et al. Time dependent changes in patellar tracking with medial parapatellar and midvastus approaches. Knee Surg Sports Traumatol Arthrosc 2005; 13 (08) 654-657
  • 12 Hofmann AA, Plaster RL, Murdock LE. Subvastus (Southern) approach for primary total knee arthroplasty. Clin Orthop Relat Res 1991; (269) 70-77
  • 13 Fauré BT, Benjamin JB, Lindsey B, Volz RG, Schutte D. Comparison of the subvastus and paramedian surgical approaches in bilateral knee arthroplasty. J Arthroplasty 1993; 8 (05) 511-516
  • 14 Liu HW, Gu WD, Xu NW, Sun JY. Surgical approaches in total knee arthroplasty: a meta-analysis comparing the midvastus and subvastus to the medial peripatellar approach. J Arthroplasty 2014; 29 (12) 2298-2304
  • 15 Mukherjee P, Press J, Hockings M. Mid-vastus vs medial para-patellar approach in total knee replacement—time to discharge. Iowa Orthop J 2009; 29: 19-22
  • 16 Fu Pei-liang, Li Xiao-hua, Wu Yu-li, Xie Qing-yun, Sun Jiu-yi, Wu Hai-shan. Comparison of midvastus and standard medial parapatellar approaches in total knee arthroplasty. J Clin Rehab Tissue Eng Res 2008; 9: 1793-1796
  • 17 Song MH, Kim BH, Ahn SJ, Yoo SH, Lee MS. Comparison of midvastus and medial parapatellar approach for total knee arthroplasty. J Korean Orthop Assoc 2005; 40 (07) 902-907
  • 18 Nutton RW, Wade FA, Coutts FJ, van der Linden ML. Short term recovery of function following total knee arthroplasty: a randomised study of the medial parapatellar and midvastus approaches. Arthritis (Egypt) 2014; 2014: 173857
  • 19 Keating EM, Faris PM, Meding JB, Ritter MA. Comparison of the midvastus muscle-splitting approach with the median parapatellar approach in total knee arthroplasty. J Arthroplasty 1999; 14 (01) 29-32
  • 20 Maru M, Akra G, McMurtry I, Port A. A prospective comparative study of the midvastus and medial parapatellar approaches for total knee arthroplasty in the early postoperative period. Eur J Orthop Surg Traumatol 2009; 19 (07) 473-476
  • 21 White Jr RE, Allman JK, Trauger JA, Dales BH. Clinical comparison of the midvastus and medial parapatellar surgical approaches. Clin Orthop Relat Res 1999; (367) 117-122
  • 22 Altay MA, Erturk C, Akmese R, Isikan UE. Midvastus versus medial parapatellar approach in total knee arthroplasty: a comparison of early functional result. Turkiye Klinikleri J Med Sci 2011; 31 (05) 1106-1112
  • 23 Dalury DF, Jiranek WA. A comparison of the midvastus and paramedian approaches for total knee arthroplasty. J Arthroplasty 1999; 14 (01) 33-37
  • 24 Bäthis H, Perlick L, Blum C, Lüring C, Perlick C, Grifka J. Midvastus approach in total knee arthroplasty: a randomized, double-blinded study on early rehabilitation. Knee Surg Sports Traumatol Arthrosc 2005; 13 (07) 545-550