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A Trial Comparing Mini-posterior Approach and Direct Anterior Approach

A Prospective, Randomized, Clinical Trial Comparing the Clinical Outcomes Following Total Hip Arthroplasty by a Single Surgeon Using Either a Mini-posterior Approach or a Direct Anterior Approach

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT01024309
Enrollment
66
Registered
2009-12-02
Start date
2009-11-30
Completion date
2013-09-30
Last updated
2014-10-30

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Osteoarthritis

Keywords

total hip arthroplasty

Brief summary

The purpose is to determine if differences exist in the attainment of functional milestones that reflect activities of daily living between mini-posterior and direct anterior approach total hip arthroplasty (THA). The investigators also hope to determine if the general health outcome after direct anterior total hip arthroplasty was better than that after mini-posterior-incision total hip arthroplasty as measured with Short Form-12 (SF-12) scores, and to evaluate variation of surgical factors of the two procedures on the basis of the operative time, component positioning, and occurrence of early complications.

Detailed description

A number of studies have compared surgical approach for total hip arthroplasty. The influence of surgical outcome as a function of approach comparing mini-posterior to direct anterior has not been reported in a randomized, prospective manner. Standard primary total hip arthroplasty (THA) can reliably alleviate pain, improve function, and improve the quality of life in a broad section of patients with end stage arthrosis of the hip. However, minimally invasive approaches, such as the direct anterior and mini-posterior approaches, have been devised with the goal of decreasing peri-operative pain, speed early postoperative function, and improve patient satisfaction with the procedure, compared with standard THA. These patient centered goals are combined with the surgeon's desire of a safe, reproducible minimally invasive procedure that has durable, properly positioned components. There are currently no prospective, randomized studies comparing the direct anterior approach to total hip arthroplasty with other minimally invasive approaches. The mini-posterior approach has been studied extensively, with promising results. Others have compared the mini-posterior approach with other minimally invasive procedures, and at the current time, has the most prospective data demonstrating its superiority as a minimally invasive approach. Pagnano performed a prospective, randomized trial comparing the early clinical results of mini -posterior THA with Two-incision THA. The results found that the early attainment of functional milestones was shorter in the mini-posterior group. The purpose is to determine if differences exist in the attainment of functional milestones that reflect activities of daily living between mini-posterior and direct anterior approach total hip arthroplasty (THA). The investigators also hope to determine if the general health outcome after direct anterior total hip arthroplasty was better than that after mini-posterior-incision total hip arthroplasty as measured with Short Form-12 (SF-12) scores, and to evaluate variation of surgical factors of the two procedures on the basis of the operative time, component positioning, and occurrence of early complications.

Interventions

PROCEDUREMini-Posterior surgical approach for total hip arthroplasty

Mini-Posterior surgical approach for total hip arthroplasty

PROCEDUREDirect Anterior surgical approach for total hip arthroplasty

Direct Anterior surgical approach for total hip arthroplasty

Sponsors

OrthoCarolina Research Institute, Inc.
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
25 Years to 80 Years
Healthy volunteers
No

Inclusion criteria

* The subject is willing and able to understand, sign and date the study specific Patient Informed Consent and Health Insurance Portability and Accountability Act (HIPPA) authorization to volunteer participation in the study. * The subject is between 25 and 80 years of age at the time of surgery. * The subject has elected to undergo primary total hip arthroplasty for osteoarthritis. * The subject is psychosocially, mentally and physically able to comply with the requirements of the study including post-operative clinical, radiographic evaluations and completion of patient questionnaires. * The subject is skeletally mature.

Exclusion criteria

* The subject has a BMI greater than 35. * The subject has had a previous total hip arthroplasty. * The subject has inflammatory arthritis. * The subject has any type of infection. * The subject has developmental dysplasia of the hip. * The subject has a known metal allergy. * The subject has an extreme offset of greater than 50 mm. * The subject has an acetabular deformity requiring advanced reconstructive techniques. * The subject has Charcot's disease. * The subject has Paget's disease * Dependence on narcotics for 6 months (or longer)

Design outcomes

Primary

MeasureTime frameDescription
Number of Days for Discontinue Assistive Devices6 weekThe primary early functional endpoint is the difference between groups in the postoperative days that patients require any assistive devices for ambulation. Lower number of days indicate better outcomes.

Secondary

MeasureTime frameDescription
Harris Hip Score3 weekThe postoperative rate of improvement in functional outcome, measured by the Harris Hip Score (HHS). The HHS was developed to assess the results of hip surgery and is intended to evaluate various hip disabilities and methods of treatment in an adult population. The domains covered are pain, function, absence of deformity, and range of motion. The function domain consists of daily activities (stair use, using public transportation, sitting, and managing shoes and socks) and gait (limp, support needed, and walking distance). Deformity takes into account hip flexion, adduction, internal rotation, and extremity length discrepancy. Range of motion measures hip flexion, abduction, external and internal rotation, and adduction. There are 10 items, which are summed to create a score out of 100. The score has a range of 0 (wost possible outcome) to 100 (best possible outcome) covering pain (0-44 points), function (0-47 points), absence of deformity (4 points), and range of motion (5 points).
Western Ontario and McMaster Universities Arthritis Index (WOMAC)3 weekTotal score from the Western Ontario and McMaster Universities Arthritis Index (WOMAC), which is a widely used set of standardized questionnaires used to evaluate the condition of patients with osteoarthritis of the knee and hip, including pain, stiffness, and physical functioning of the joints. WOMAC measures five items for pain (score range 0-20), two for stiffness (range 0-8), and 17 for functional limitation (range 0-68). Physical functioning questions cover everyday activities such as stair use, standing up from a sitting or lying position, standing, bending, walking, getting in/out of a car, shopping, putting on or taking off socks, lying in bed, getting in or out of a bath, sitting, and heavy and light household duties. It produces three subscale scores (pain, stiffness, and physical function) and a total score. These scores are transformed into a scale of 0 (worst possible outcome) to 100 (best possible outcome) for ease of interpretation and comparison with other studies.
Abduction Angle6 wkAbduction angle is a radiographic measure of implant position. 40 degrees of abduction is optimal. 30-50 degrees of anteversion indicates correct placement of prosthetic joint. Values closer to 40 degrees indicate better placement.
Anteversion Angle6 weekAnteversion angle is a radiographic measure of implant position. 35 degrees of anteversion is optimal. 25-45 degrees of anteversion indicates correct placement of prosthetic joint. Values closer to 35 degrees indicate better placement.
WOMAC6 weekTotal score from the Western Ontario and McMaster Universities Arthritis Index (WOMAC), which is a widely used set of standardized questionnaires used to evaluate the condition of patients with osteoarthritis of the knee and hip, including pain, stiffness, and physical functioning of the joints. WOMAC measures five items for pain (score range 0-20), two for stiffness (range 0-8), and 17 for functional limitation (range 0-68). Physical functioning questions cover everyday activities such as stair use, standing up from a sitting or lying position, standing, bending, walking, getting in/out of a car, shopping, putting on or taking off socks, lying in bed, getting in or out of a bath, sitting, and heavy and light household duties. It produces three subscale scores (pain, stiffness, and physical function) and a total score. These scores are transformed into a scale of 0 (worst possible outcome) to 100 (best possible outcome) for ease of interpretation and comparison with other studies.

Countries

United States

Participant flow

Recruitment details

66 volunteer participants were enrolled during routine clinical practice of the principal investigator between the dates of 12/8/2009 and 10/9/2012.

Pre-assignment details

12 patients withdrew participation prior to randomization

Participants by arm

ArmCount
Mini-Posterior Approach
Mini-Posterior surgical approach for total hip arthroplasty
35
Direct Anterior Approach
Direct Anterior surgical approach for total hip arthroplasty
31
Total66

Withdrawals & dropouts

PeriodReasonFG000FG001
Overall StudyPhysician Decision40
Overall StudyWithdrawal by Subject44

Baseline characteristics

CharacteristicDirect Anterior ApproachMini-Posterior ApproachTotal
Age, Categorical
<=18 years
0 Participants0 Participants0 Participants
Age, Categorical
>=65 years
14 Participants17 Participants31 Participants
Age, Categorical
Between 18 and 65 years
17 Participants18 Participants35 Participants
Age, Continuous63.4 years
STANDARD_DEVIATION 8.6
64.2 years
STANDARD_DEVIATION 9.4
63.8 years
STANDARD_DEVIATION 9
Region of Enrollment
United States
31 participants35 participants66 participants
Sex: Female, Male
Female
16 Participants18 Participants34 Participants
Sex: Female, Male
Male
15 Participants17 Participants32 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
— / —— / —
other
Total, other adverse events
1 / 271 / 27
serious
Total, serious adverse events
3 / 271 / 27

Outcome results

Primary

Number of Days for Discontinue Assistive Devices

The primary early functional endpoint is the difference between groups in the postoperative days that patients require any assistive devices for ambulation. Lower number of days indicate better outcomes.

Time frame: 6 week

Population: A total of 54 participants returned for follow-up at 6 weeks. The remaining patients did not return to the clinic for follow-up at 6 weeks.

ArmMeasureValue (MEDIAN)
Mini-Posterior ApproachNumber of Days for Discontinue Assistive Devices28 days
Direct Anterior ApproachNumber of Days for Discontinue Assistive Devices22 days
p-value: 0.04Wilcoxon (Mann-Whitney)
Secondary

Abduction Angle

Abduction angle is a radiographic measure of implant position. 40 degrees of abduction is optimal. 30-50 degrees of anteversion indicates correct placement of prosthetic joint. Values closer to 40 degrees indicate better placement.

Time frame: 6 wk

Population: A total of 54 participants returned for follow-up at 6 weeks. The remaining patients did not return to the clinic for follow-up at 6 weeks.

ArmMeasureValue (MEDIAN)
Mini-Posterior ApproachAbduction Angle40 degrees
Direct Anterior ApproachAbduction Angle38 degrees
p-value: 0.22Wilcoxon (Mann-Whitney)
Secondary

Anteversion Angle

Anteversion angle is a radiographic measure of implant position. 35 degrees of anteversion is optimal. 25-45 degrees of anteversion indicates correct placement of prosthetic joint. Values closer to 35 degrees indicate better placement.

Time frame: 6 week

Population: A total of 54 participants returned for follow-up at 6 weeks. The remaining patients did not return to the clinic for follow-up at 6 weeks.

ArmMeasureValue (MEDIAN)
Mini-Posterior ApproachAnteversion Angle29 degrees
Direct Anterior ApproachAnteversion Angle26 degrees
p-value: 0.0029Wilcoxon (Mann-Whitney)
Secondary

Harris Hip Score

The postoperative rate of improvement in functional outcome, measured by the Harris Hip Score (HHS). The HHS was developed to assess the results of hip surgery and is intended to evaluate various hip disabilities and methods of treatment in an adult population. The domains covered are pain, function, absence of deformity, and range of motion. The function domain consists of daily activities (stair use, using public transportation, sitting, and managing shoes and socks) and gait (limp, support needed, and walking distance). Deformity takes into account hip flexion, adduction, internal rotation, and extremity length discrepancy. Range of motion measures hip flexion, abduction, external and internal rotation, and adduction. There are 10 items, which are summed to create a score out of 100. The score has a range of 0 (wost possible outcome) to 100 (best possible outcome) covering pain (0-44 points), function (0-47 points), absence of deformity (4 points), and range of motion (5 points).

Time frame: 3 week

Population: A total of 53 participants returned for follow-up at 3 weeks. The remaining patients did not return to the clinic for follow-up at 3 weeks.

ArmMeasureValue (MEDIAN)
Mini-Posterior ApproachHarris Hip Score81 units on a scale
Direct Anterior ApproachHarris Hip Score86.5 units on a scale
p-value: 0.08Wilcoxon (Mann-Whitney)
Secondary

Harris Hip Score

The postoperative rate of improvement in functional outcome, measured by the Harris Hip Score (HHS). The HHS was developed to assess the results of hip surgery and is intended to evaluate various hip disabilities and methods of treatment in an adult population. The domains covered are pain, function, absence of deformity, and range of motion. The function domain consists of daily activities (stair use, using public transportation, sitting, and managing shoes and socks) and gait (limp, support needed, and walking distance). Deformity takes into account hip flexion, adduction, internal rotation, and extremity length discrepancy. Range of motion measures hip flexion, abduction, external and internal rotation, and adduction. There are 10 items, which are summed to create a score out of 100. The score has a range of 0 (wost possible outcome) to 100 (best possible outcome) covering pain (0-44 points), function (0-47 points), absence of deformity (4 points), and range of motion (5 points).

Time frame: 6 week

Population: 54 participants returned for follow-up at 6 weeks. A total of 5 participants did not complete the Harris Hip Score instrument in its entirety at this appointment and, thus, were excluded from the analysis. The remaining patients did not return to the clinic for follow-up at 6 weeks.

ArmMeasureValue (MEDIAN)
Mini-Posterior ApproachHarris Hip Score93 units on a scale
Direct Anterior ApproachHarris Hip Score97 units on a scale
p-value: 0.13Wilcoxon (Mann-Whitney)
Secondary

Harris Hip Score

The postoperative rate of improvement in functional outcome, measured by the Harris Hip Score (HHS). The HHS was developed to assess the results of hip surgery and is intended to evaluate various hip disabilities and methods of treatment in an adult population. The domains covered are pain, function, absence of deformity, and range of motion. The function domain consists of daily activities (stair use, using public transportation, sitting, and managing shoes and socks) and gait (limp, support needed, and walking distance). Deformity takes into account hip flexion, adduction, internal rotation, and extremity length discrepancy. Range of motion measures hip flexion, abduction, external and internal rotation, and adduction. There are 10 items, which are summed to create a score out of 100. The score has a range of 0 (wost possible outcome) to 100 (best possible outcome) covering pain (0-44 points), function (0-47 points), absence of deformity (4 points), and range of motion (5 points).

Time frame: 12 month

Population: A total of 37 participants returned for follow-up at 12 months. The remaining patients did not return to the clinic for follow-up at 12 months.

ArmMeasureValue (MEDIAN)
Mini-Posterior ApproachHarris Hip Score97.5 units on a scale
Direct Anterior ApproachHarris Hip Score98 units on a scale
p-value: 0.23Wilcoxon (Mann-Whitney)
Secondary

Western Ontario and McMaster Universities Arthritis Index (WOMAC)

Total score from the Western Ontario and McMaster Universities Arthritis Index (WOMAC), which is a widely used set of standardized questionnaires used to evaluate the condition of patients with osteoarthritis of the knee and hip, including pain, stiffness, and physical functioning of the joints. WOMAC measures five items for pain (score range 0-20), two for stiffness (range 0-8), and 17 for functional limitation (range 0-68). Physical functioning questions cover everyday activities such as stair use, standing up from a sitting or lying position, standing, bending, walking, getting in/out of a car, shopping, putting on or taking off socks, lying in bed, getting in or out of a bath, sitting, and heavy and light household duties. It produces three subscale scores (pain, stiffness, and physical function) and a total score. These scores are transformed into a scale of 0 (worst possible outcome) to 100 (best possible outcome) for ease of interpretation and comparison with other studies.

Time frame: 3 week

Population: A total of 53 participants returned for follow-up at 3 weeks. The remaining patients did not return to the clinic for follow-up at 3 weeks.

ArmMeasureValue (MEDIAN)
Mini-Posterior ApproachWestern Ontario and McMaster Universities Arthritis Index (WOMAC)91.48 units on a scale
Direct Anterior ApproachWestern Ontario and McMaster Universities Arthritis Index (WOMAC)87.20 units on a scale
p-value: 0.04Wilcoxon (Mann-Whitney)
Secondary

WOMAC

Total score from the Western Ontario and McMaster Universities Arthritis Index (WOMAC), which is a widely used set of standardized questionnaires used to evaluate the condition of patients with osteoarthritis of the knee and hip, including pain, stiffness, and physical functioning of the joints. WOMAC measures five items for pain (score range 0-20), two for stiffness (range 0-8), and 17 for functional limitation (range 0-68). Physical functioning questions cover everyday activities such as stair use, standing up from a sitting or lying position, standing, bending, walking, getting in/out of a car, shopping, putting on or taking off socks, lying in bed, getting in or out of a bath, sitting, and heavy and light household duties. It produces three subscale scores (pain, stiffness, and physical function) and a total score. These scores are transformed into a scale of 0 (worst possible outcome) to 100 (best possible outcome) for ease of interpretation and comparison with other studies.

Time frame: 6 week

Population: A total of 54 participants returned for follow-up at 6 weeks. 3 participants did not complete the WOMAC in its entirety at this appointment and, thus, were excluded from the analysis. The remaining patients did not return to the clinic for follow-up at 6 weeks.

ArmMeasureValue (MEDIAN)
Mini-Posterior ApproachWOMAC95.72 units on a scale
Direct Anterior ApproachWOMAC95.41 units on a scale
p-value: 0.29Wilcoxon (Mann-Whitney)
Secondary

WOMAC

Total score from the Western Ontario and McMaster Universities Arthritis Index (WOMAC), which is a widely used set of standardized questionnaires used to evaluate the condition of patients with osteoarthritis of the knee and hip, including pain, stiffness, and physical functioning of the joints. WOMAC measures five items for pain (score range 0-20), two for stiffness (range 0-8), and 17 for functional limitation (range 0-68). Physical functioning questions cover everyday activities such as stair use, standing up from a sitting or lying position, standing, bending, walking, getting in/out of a car, shopping, putting on or taking off socks, lying in bed, getting in or out of a bath, sitting, and heavy and light household duties. It produces three subscale scores (pain, stiffness, and physical function) and a total score. These scores are transformed into a scale of 0 (worst possible outcome) to 100 (best possible outcome) for ease of interpretation and comparison with other studies.

Time frame: 12 month

Population: A total of 37 participants returned for follow-up at 12 months. The remaining patients did not return to the clinic for follow-up at 12 months.

ArmMeasureValue (MEDIAN)
Mini-Posterior ApproachWOMAC97.37 units on a scale
Direct Anterior ApproachWOMAC97.37 units on a scale
p-value: 0.49Wilcoxon (Mann-Whitney)

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026