Comparison of Muscle Strength and Functional Status of Patients with Operated and Non-Operated Chronic Total Anterior Cruciate Ligament Injury
- Authors: Arda Bulut P., Ayyıldız A., Çiftci İnceoğlu S., Yılmaz F., Şahinkaya T., Eren O.T., Kuran B.
- Section: СLINICAL STUDIES
- Submitted: 20.05.2025
- Accepted: 30.07.2025
- Published: 30.07.2025
- URL: https://journal.rniito.org/jour/article/view/17721
- DOI: https://doi.org/10.17816/2311-2905-17721
- ID: 17721
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Abstract
Purpose: The study aims to compare young and active patients diagnosed with total ACL injury, with and without surgery, in terms of pain, knee functional results, quality of life, quadriceps and hamstring muscle strength, and thickness differences with ultrasonography in the chronic period.
Methods: Male patients aged 18 to 40 with total ACL rupture, with or without surgery, were evaluated during chronic period. The study evaluated patients' pain levels, joint range of motion, thigh circumference measurements using the visual analog scale, and quadriceps and hamstring muscle thickness measurements using ultrasonography. Functionality was assessed using the single-step jump, Lysholm Knee Scale, and Anterior Cruciate Ligament Quality of Life Questionnaire.
Results: The study involved 21 non-operated and 20 operated patients. The rate of rehabilitation was significantly higher in the operated group, despite no significant difference between the groups in terms of the injured side. Furthermore, the operated group exhibited a statistically significant difference in thigh circumference between the right and left sides. The evaluation conducted by USG found a significant difference in hamstring muscle thickness between the operated group and the control group. However, there was no significant difference observed between the groups in terms of knee functionality, as indicated by the Lysholm knee scale and jump tests, and flexor and extensor isokinetic muscle strengths.
Conclusion: Patients with ACL injuries may exhibit no significant difference between knee functionality and isokinetic muscle strength evaluations, regardless of whether they have undergone surgery or not. However, the group that underwent surgery showed significant muscle loss.
Full Text
Comparison of Muscle Strength and Functional Status of Patients with Operated and Non-Operated Chronic Total Anterior Cruciate Ligament Injury
ABSTRACT
Purpose: The study aims to compare young and active patients diagnosed with total ACL injury, with and without surgery, in terms of pain, knee functional results, quality of life, quadriceps and hamstring muscle strength, and thickness differences with ultrasonography in the chronic period.
Methods: Male patients aged 18 to 40 with total ACL rupture, with or without surgery, were evaluated during chronic period. The study evaluated patients' pain levels, joint range of motion, thigh circumference measurements using the visual analog scale, and quadriceps and hamstring muscle thickness measurements using ultrasonography. Functionality was assessed using the single-step jump, Lysholm Knee Scale, and Anterior Cruciate Ligament Quality of Life Questionnaire.
Results: The study involved 21 non-operated and 20 operated patients. The rate of rehabilitation was significantly higher in the operated group, despite no significant difference between the groups in terms of the injured side. Furthermore, the operated group exhibited a statistically significant difference in thigh circumference between the right and left sides. The evaluation conducted by USG found a significant difference in hamstring muscle thickness between the operated group and the control group. However, there was no significant difference observed between the groups in terms of knee functionality, as indicated by the Lysholm knee scale and jump tests, and flexor and extensor isokinetic muscle strengths.
Conclusion: Patients with ACL injuries may exhibit no significant difference between knee functionality and isokinetic muscle strength evaluations, regardless of whether they have undergone surgery or not. However, the group that underwent surgery showed significant muscle loss.
Keywords: anterior cruciate ligament injury, functionality, isokinetic muscle strength, surgery
INTRODUCTION
The anterior cruciate ligament (ACL) is the primary stabilizer that prevents forward translation of the tibia [1]. ACL injury is the most common ligament injury in the knee [2]. In America, more than 200,000 cases occur annually [1]. ACL injuries are most common in young and physically active individuals, with 65% of injuries occurring during sports and 70% occurring with non-contact mechanisms [3, 4].
The objective of treating ACL injuries is to alleviate pain and instability in the knee and restore knee function [1]. However, the optimal treatment for ACL injuries is not yet definitive. Although surgical treatment is commonly performed, it may increase the risk of complications. Furthermore, surgical intervention improves static knee stability. Studies have shown that there is no significant difference in knee functionality, performance, or objective muscle strength of the muscles surrounding the knee between patients who have undergone surgery and those who have not [3, 5-7].
This study aims to compare knee functional results, quality of life, quadriceps and hamstring muscle strengths, and muscle thickness differences using ultrasonography between patients who have undergone surgery and those who have not.
MATERIALS AND METHODS
The study involved male patients aged 18-40 who had experienced a total ACL rupture on knee MRI within the past 6 months. Only patients with unilateral ACL rupture who had undergone surgery with hamstring autograft and anatomical-single band technique or had at least 6 months since the ACL injury were included. Furthermore, patients with a Tegner Activity Scale (TAS) score of ≥4 were considered for the study. The study excluded patients with specific conditions, such as Posterior Cruciate Ligament (PCL) rupture accompanying total ACL rupture, articular cartilage damage, Stage III collateral ligament damage, accompanying fracture, traumatic injury or surgery on the other knee, partial anterior cruciate rupture, a history of recurrent ACL surgery, and intra-articular effusion.
The design of the study was planned as a cross-sectional, single-blind, analytical study. This research has been approved by the Ethical Committee of XXX Hospital (decision date: 15.03.16 number: 1122). The written informed consent was obtained from the patients. Our research was completed in accordance with the principles of the Declaration of Helsinki.
The study participants provided detailed information on their age, occupation, education level, weight, height, body mass index, presence of trauma, injured knee side, dominant knee, date of injury, date of operation, presence of rehabilitation, and slipping sensation. Pain levels were evaluated using the Visual Analog Scale (VAS). Additionally, the front part of each participant's knee was covered with tape prior to evaluation. The investigators performed the physical examination, ultrasonography (USG), and isokinetic evaluation while blinded. Joint range of motion (ROM) measurements were taken using a goniometer on a hard surface, and the degrees of flexion and extension were recorded. TAS was used to determine the pre-injury activity levels of the patients. Additionally, the anterior drawer test was utilized to compare the operated and non-operated groups. Thigh circumference measurements were confidently taken bilaterally in centimeters using a tape measure, at the same distance from the medial malleolus of the tibia. The study measured the hamstring and quadriceps muscle thicknesses twice in both legs of the patients using USG, following the methodology described in the literature. The quadriceps muscle thickness, which includes the vastus intermedius and rectus femoris, was measured with the knee in full extension while the patient was in a supine position. The midpoint of the patella was marked using 50% of the distance between the spina iliaca anterior superior (SIAS) and the midpoint of the patella (Figure 1). The vastus intermedius and rectus femoris muscles were each measured twice at the same point for both legs, and the average of the two measurements was taken for each leg. The patient was positioned prone and the knees were extended to measure hamstring muscle thickness. The study measured the hamstring surface cross-sectional area and the difference in muscle thickness between both legs. Measurements were taken twice from the same point for each leg and the average was calculated separately for each leg. The maximum cross-sectional area of the hamstring was found at the greater trochanter and 60% of the lateral knee (Figure 2).
To evaluate the patients' functional status, we conducted single-leg jump tests twice on each extremity and completed the Lysholm Knee Scale (LKS). Our study measured the distance and time of a single-leg 6-meter jump. The farthest distance jumped with one leg while wearing sports shoes on hard ground determined the single-leg jump distance. Using the Limb Symmetry Index (LSI), the jump test evaluated both extremities for symmetry, with results of 90% and above considered symmetrical and results below 90% considered asymmetrical. The single leg 6-meter jump test required patients to jump 6 meters on one leg, and the time was measured with a stopwatch. The test was performed twice for both extremities, and the average time in seconds was recorded.
The Anterior Cruciate Ligament - Quality of Life Questionnaire (ACL-QOL) assessed the quality of life for both groups of patients. A higher score indicates a better quality of life. The questionnaire was completed by all patients, and the average score for each of the five subheadings was calculated by averaging the scores of the items.
The study conducted an isokinetic knee flexion and extension muscle strength test using a Cybex-350Ⓡ dynamometer, with the assessor blinded. The patients were positioned on the device with their trunks at an angle of 80-85° with the hips and fastened to the chair with tapes over the trunk, pelvis, and thighs (Figure 3). Additionally, patients held onto the handles on both sides of the dynamometer seat during the test. Before the test, each patient completed a 10-minute warm-up program on a bicycle ergometer. Following this, the patients underwent a 3-minute stretching routine for their quadriceps and hamstring muscles before being tested. The test protocol consisted of 4 trials with 4 repetitions at a speed of 60o/sec, and 5 trials with 20 test repetitions at a speed of 240o/sec. Throughout the test, verbal motivation was provided to the patients. At the end of the test, peak torque values, percentages of peak torque values according to body weight (Peak Torque/% Body Weight (PT/% BW)) and total work done (Total Work (TW)) were recorded for both knees.
The research data was analyzed using SPSS (Statistical Package for Social Sciences) for Windows 22.0 (SPSS Inc, Chicago, IL). Descriptive statistics are presented as mean±standard deviation, median (minimum-maximum), frequency distribution, and percentage. Categorical variables were evaluated using Pearson Chi-Square Test, Yates Corrected Chi-Square Test, and Fisher's Exact Test. The normal distribution suitability of the variables was examined using the Shapiro-Wilk Test. Statistical significance between two independent groups for variables that complied with normal distribution was determined using the Student's T Test. For variables that did not comply with normal distribution, the Mann-Whitney U Test was used. The relationship between variables was evaluated using Spearman Correlation Analysis. We accepted a statistical significance level of p<0.05.
RESULTS
The study analyzed 41 patients with ACL rupture, with 51.2% (21 patients) undergoing surgery and 48.8% (20 patients) not. The demographic data of the patients is presented in Table 1. No statistically significant differences were found between the age, height, weight, BMI, education level, time since injury, injured tissues, affected and dominant knee, pre-injury TAS, duration, and type of rehabilitation for those receiving rehabilitation (p>0.05). However, those who underwent surgery had a significantly higher rate of rehabilitation compared to those who did not undergo surgery (p<0.05). The patients' operation-related characteristics were examined, revealing a median time of 30 months (7-42 months) since the operation and a median time of 5 months (1-26 months) from injury to operation. The majority of patients (71.4%) underwent a 'hamstring autograft + meniscus repair', while the remaining 28.6% underwent only a 'hamstring autograft'.
The examination results demonstrate a statistically significant increase in anterior drawer test positivity in non-operated patients (p<0.05). Moreover, non-operated patients exhibited a significantly lower diameter difference between the affected and intact thighs compared to operated patients (p<0.05). Lastly, operated patients demonstrated a significantly higher difference in hamstring muscle thickness between the affected and healthy side (p<0.05). There was no significant difference in quadriceps muscle thickness between the affected and unaffected areas, as well as affected hamstring muscle thickness (p>0.05). However, the operated group demonstrated a significantly higher difference in intact hamstring muscle thickness and healthy/affected side hamstring muscle thickness compared to the non-operated group (p<0.05). No statistically significant differences were found between the study groups in terms of slipping sensation, right and left thigh diameter, LKS score, knee function degree according to LKS, and asymmetry according to the distanced single-step jump test (p>0.05). Furthermore, all patients exhibited symmetrical single-leg 6-meter jumps during the test time (Table 2).
The LKS score was significantly higher in the rehabilitation group (p<0.05) when compared to non-operated patients who did not receive rehabilitation. Additionally, the rates of being symmetrical in the single-leg hop test and having good to excellent knee function were significantly higher among non-operated patients who received rehabilitation (p<0.05). No statistically significant difference was detected between the non-operated patients who received rehabilitation and those who did not in terms of the anterior drawer test, slipping sensation, affected and intact thigh diameter and differences, affected and intact quadriceps femoris and hamstring muscle thickness (p>0.05) (Table 2).
The sub-factor scores of ACL-QOL for 'work-related concerns', 'hobbies, participation in sports or competition', and 'social and emotional' as well as the total score of the non-operated patients were significantly lower than those of the operated patients (p<0.05). There was no significant difference between the groups in terms of the 'symptoms and physical complaints' and 'lifestyle' sub-factor scores of the ACL-QOL (p>0.05). In non-operated patients who received rehabilitation, the ACL-QOL total score and the sub-factor scores of symptoms and physical complaints, hobbies, participation in sports or competitions, lifestyle, social, and emotional were significantly higher than in non-operated patients who did not receive rehabilitation. (p<0.05) (Table 2).
No statistically significant differences were found in isokinetic measurements for extension and flexion between the two groups (p>0.05). However, a statistically significant difference was observed in PT/BW at 60o/sec angular speed, PT/BW at 240o/sec, TW, and TW/BW values at 240o/sec on the affected side during flexion when comparing non-operated patients who received rehabilitation to those who did not (p<0). There was no significant difference found in all isometric measurements in extension (p>0.05) and other isometric measurements in flexion. Furthermore, there was no significant difference observed between non-operated patients who received rehabilitation and those who did not, in terms of hamstring/quadriceps ratios at 60o/sec and 240o/sec on both the affected and healthy sides. (p>0.05).
Table 3 demonstrates the relationship between the ACL-QoL questionnaire and various factors, including age, body mass index, injury duration, TAS, LKS score, and thigh diameter and muscle thickness differences, based on the operating status. The LKS score and the ACL-QoL Questionnaire total score, as well as the scores for symptoms and physical complaints, work-related concerns, hobbies, participation in sports or competitions, lifestyle, and social and emotional factors were all evaluated and found to have a strong correlation (r=0.71, r=0.74, r=0.67, r=0.71, r=0.56, r=0.61, respectively; p<0.05) (Table 3). The study clearly demonstrates a positive and statistically significant relationship between the sub-factor scores of the operated patients. A positive and strong correlation was found in non-operated patients between LKS score and ACL-QoL questionnaire total score, as well as symptoms and physical complaints, work-related concerns, hobbies, participation in sports or competitions, lifestyle, and social and emotional sub-factor scores (r=0.68, r=0.63, r=0.58, r=0.68, r=0.56, r=0.61; p<0.05, respectively) (Table 3).
The relationship between affected side isokinetic measurements and ACL-QOL scores of operated and non-operated patients is also shown in Table 4.
DISCUSSION
Our study only included male patients to ensure consistency with the trend of a high prevalence of male patients in studies on ACL injuries. This is supported by Sanders et al. (2016) who reported a higher incidence of ACL injuries in men than in women in the general population (81.7 per 100,000 men, 55.3 women, P = 0.001) [8].
Patients with ACL lesions commonly experience pain and a slipping sensation. Pain is caused by hemarthrosis in the acute period and mostly by the development of osteoarthritis in the chronic period. It is important to note that a study conducted by Moksnes et al. found no significant difference in VAS values between operative and non-operative ACL injuries, indicating that non-operative treatment may be a viable option for some patients [2]. In a meta-analysis by Smith et al., it was determined that the development of osteoarthritis after ACL injury occurred more after 5 years [3]. Our study evaluated patients within the first 5 years after the injury, consistent with the literature. We found no significant difference between the groups in terms of pain and slipping sensation.
The main objective of conducting a physical examination on patients with ACL injuries is to assess the stability of the knee. In this study, we utilized the Anterior Drawer Test to evaluate knee stability and found a significantly higher rate of positive tests in the non-operated group, indicating that the knees of patients who underwent surgery were more stable. Our findings are consistent with those of Moksnes et al. who also found better knee stability in patients who underwent surgery [2]. Studies objectively evaluating stability using devices such as KT-1000 or KT-2000 found the operated group to be stable [2, 9]. Furthermore, there was no significant difference in functionality between the groups despite the operated group being more stable upon physical examination [5, 6, 9].
Operated and non-operated patients showed differences in muscle thickness and isokinetic measurements in thigh circumference. It is important to note that muscle thickness is correlated with muscle strength, as stated by Abe et al. [10]. Our study found that although the hamstring muscle thicknesses differed between the two groups, no difference was detected in the isokinetic evaluation or flexor muscle group strengths. Muscle thickness is not necessarily correlated with muscle strength. Age and gender are among the factors that may impact muscle strength.
Meniscus damage commonly accompanies ACL injuries. Meniscus damage accompanies acute ACL injuries in 16-84.7% of cases, as shown by research [11, 12]. Additionally, a 6-year cohort study conducted by Duchman et al. found that this value was 65.3% [13]. Our study found that meniscus damage was present in 15 patients (71.4%) in the operated group and 16 patients (80%) in the non-operated group.
In a prospective randomized controlled study conducted by Frobell et al., 120 active adult patients aged 18-35 were included. At the 10th week, 61 patients underwent early ACL reconstruction, while reconstruction was postponed and performed if necessary in the remaining 59 patients. Early surgical treatment resulted in significantly less instability when evaluated by Lachman and Pivot-shift tests, with no significant difference in pain, symptoms, and Knee Injury and Osteoarthritis Outcome Score (KOOS), SF-36 QoL questionnaire, and TAS when evaluating 5-year results. Additionally, there was no significant difference between the groups in terms of osteoarthritis development [7]. Grindem et al. conducted a study examining the 1-year results of active rehabilitation patients with ACL injuries who underwent surgery and those who did not. The non-operative group showed significantly better results in four jump tests, the Knee Outcome Survey Activities of Daily Living Scale (KOS-ADLS), and International Knee Documentation Committee (IKDC)-2000 scores, despite showing more laxity in KT-1000 measurements. Knee function and return to sports did not differ between the two groups [14].
These findings demonstrate the reliability and consistency of isokinetic tests and devices in providing objective data for the follow-up of patients with ACL injuries. The study results indicate that there was no statistically significant difference between the flexion and extension muscle peak torques, peak torque/body weight values at an angular speed of 60o/sec, and the flexion and extension peak torque, peak torque/body weight values and total work at 240o/sec in the operated and non-operated groups. Our findings are supported by studies in the literature. Grindem et al. conducted a 2-year follow-up in 2014 and found no significant difference in knee flexion and extension muscle strength and knee function between operative and non-operatively treated patients, which is consistent with our study [6]. Our study supports Smith et al.'s meta-analysis, which found no significant difference between flexion and extension muscle strengths in the one- to four-year results [3].
Quadriceps weakness is common in ACL injuries and its etiology is multifactorial. There is less loss of strength in the hamstring muscles after ACL injury compared to the quadriceps [15]. This supports the hypothesis that knee flexors are ACL agonists and that flexor muscle strength is less affected by compensatory mechanisms after ACL injury [16]. Neurological dysfunction was found to be less effective in the knee flexors than in the knee extensors in patients with ACL injuries, as concluded by Konishi et al. [17]. Additionally, patients who underwent reconstruction with hamstring and patellar tendon autograft showed no difference in muscle strength [18].
The H/Q ratio assesses the balance between the hamstring and quadriceps muscles, and changes in this ratio may increase the risk of developing osteoarthritis after an ACL injury [19]. Kim et al.'s meta-analysis supports the existence of a protective mechanism in the knee after an ACL injury that reduces quadriceps isokinetic strength and theoretically increases hamstring strength to protect against tibial anterior translation. The research demonstrates that quadriceps muscle strength loss is three times greater than hamstring muscle strength loss, leading to an increased H/Q ratio in the injured leg compared to the healthy leg [20]. Our study shows that the average H/Q ratios of the injured knees in both the operated and non-operated groups at 60/sec and 240/sec were higher than those of the healthy knee.
In a review in the literature, no difference was found between surgical treatment and conservative treatment in the treatment of ACL injuries in adults in terms of KOOS score, SF-36 quality of life score and return to sports activity rates, but it was stated that this review was at a low level of evidence [21]. Our study found that ACL-QOL results were significantly better in the group that underwent surgery compared to the non-operated group. The subheadings that showed significant differences were mostly related to the patients' emotional state. The patients' psychological state, fear of re-injury, and kinesiophobia may have also influenced these differences. Notably, Sonesson et al. conducted a study that demonstrated improved return-to-sport rates when rehabilitation included psychological factors such as motivation [22]. Psychological factors, such as kinesiophobia and fear of injury, play a significant role in determining whether an individual returns to their pre-injury level of sports activity [23].
Rehabilitation is a crucial factor that impacts the outcomes of both conservatively treated and surgically treated patients. These findings suggest that rehabilitation may not be the sole determining factor in patient outcomes and that other factors should be considered as well. Our study found that the rate of rehabilitation was significantly higher in the surgical group. However, despite the higher number of patients receiving rehabilitation in the surgical group, no significant difference was detected in functionality (LKS and jump tests) and isokinetic test results. There were no significant differences in symptoms (VAS, slipping sensation) and physical examination findings (anterior drawer test, ROM, thigh diameter differences) between the non-operated patients who received rehabilitation and those who did not. Nevertheless, patients who received rehabilitation demonstrated significantly better results in LKS and jump tests, which evaluate knee functionality. Our study found a strong and statistically significant positive correlation between all subheadings of ACL-QOL and LKS in both the operated and non-operated groups. This confirms the findings of Kınıklı et al. (2015), who reported a fair correlation (r=0.23) between LKS and ACL-QOL in their Turkish translation of the questionnaire [24].
When we examined the literature, we could not find any studies examining the correlation between ACL-QOL and isokinetic muscle strength. However, the relationship between isokinetic muscle strength and the SF-36 QoL questionnaire was evaluated. In this study conducted by Marn-Vukadinovic et al., a negative correlation was found between knee extensor weakness (60o/sec PT) and physical function and social function (r = -0.59, P < 0.01 and r = -0.43, p < 0.01, respectively) [25]. Our study confirms that a reduction in knee extensor muscle strength is linked to a decline in the quality of life of knee injury patients. Furthermore, we examined the relationship between ACL-QoL subheadings and isokinetic muscle strength measurements for both the operated and non-operated groups. The study found a significant positive correlation between extension PT and PT/BW on the affected side of the operated patients at a speed of 60o/sec, extension PT/BW at 240o/sec, and all subheadings of ACL-QoL. These results demonstrate the relationship between these variables. The correlation analysis of the non-operated group showed a statistically significant relationship between the 'symptoms and physical complaints' subheading of ACL-QoL and the affected side with 240/sec extension PT, PT/BW, TW, TW/BW and 60/sec flexion PT, PT/BW. Furthermore, the isometric strengths of PT, PT/BW, TW, TW/BW at a speed of 240/sec exhibited a positive difference. The operated group did not show a significant relationship between the other subheadings of ACL-QOL.
The main limitations of our study are the relatively small number of patients in the groups, the lack of pre-injury data, and the fact that it was a cross-sectional study. Prospective studies with larger patient groups are needed in the future.
In conclusion, there were no significant differences in knee functionality and isokinetic muscle strength between the operated and non-operated patients. However, it is worth noting that the quality of life was better in the operated group, which contradicts the literature. This could be due to the higher number of patients receiving rehabilitation in the operated group and the fact that the differing subheadings were more related to emotional and kinesiophobia.
Main Points:
- The study compares knee functional results, quality of life, muscle strengths, and muscle thickness using ultrasonography between patients with anterior cruciate ligament (ACL) injuries who have undergone surgery and those who have not.
- No significant differences were found in knee functionality and isokinetic muscle strength between operated and non-operated patients, although operated patients had better overall quality of life scores.
- Non-operated patients exhibited a significantly lower diameter difference between the affected and intact thighs, and higher anterior drawer test positivity compared to operated patients.
- Rehabilitation significantly improved the quality of life and knee functionality scores, especially in non-operated patients, emphasizing the importance of comprehensive post-injury rehabilitation programs.
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TABLES
Table 1: Demographic Characteristic of Patients
| Operated (n=21) | Non-Operated (n=20) | p | |||
Age (year), ±S | 29,43±5,01 | 28,45±7,02 | 0,611a | |||
Body Weight (kg), ±S | 81,91±15,16 | 74,08±9,71 | 0,057a | |||
Height (cm), ±S | 175,81±7,43 | 173,90±6,84 | 0,398a | |||
BMI (kg/m2), ±S | 26,36±3,82 | 24,50±2,93 | 0,089a | |||
Education, n (%) |
|
|
| |||
| High School | 12 (57,1) | 11 (55,0) | 0,890b | ||
| University | 9 (42,9) | 9 (45,0) | |||
Time Since Injury (month), median (min-max) | 35 (10-58) | 20,5 (5-60) | 0,053c | |||
Injured Tissue, n (%) |
|
|
| |||
| Anterior Cruciate Ligament | 6 (28,6) | 4 (20,0) | 0,719d | ||
| Anterior Cruciate Ligament +Meniscus | 15 (71,4) | 16 (80,0) | |||
Injured Knee Side, n (%) |
|
|
| |||
| Right | 8 (38,1) | 14 (70,0) | 0,083b | ||
| Left | 13 (61,9) | 6 (30,0) | |||
Dominant Knee, n (%) |
|
|
| |||
| Right | 18 (85,7) | 20 (100) | 0,232d | ||
| Left | 3 (14,3) | 0 | |||
Rehabilitation Status, n (%) |
|
|
| |||
| Non-taken | 3 (14,3) | 10 (50,0) | 0,034b | ||
| Taken | 18 (85,7) | 10 (50,0) | |||
|
| Rehabilitation Duration (month), median (min-max) | 2 (0,5-14) | 4 (0,5-12) | 0,944c | |
|
| Rehabilitation Program, n (%) |
|
|
| |
|
|
| Home Exercise Program | 9 (50,0) | 7 (70,0) | 0,434d |
|
|
| On Physiotherapist Supervision | 9 (50,0) | 3 (30,0) | |
Tegner Activity Scale, median (min-max) | 7 (5-9) | 7 (3-9) | 0,739c | |||
: Mean; S: Standard Deviation; n: Patient Number; BMI: Body Mass Index a: Student’s T Test; b: Yates Corrected Chi-Square Test; c: Mann-Whitney U Test; d: Fisher Exact Test | ||||||
Table 2: Distribution of Laxity Status, Functional Status, Quality of Life, Muscle Diameter and Thickness Among Study Groups
| Operated (n=21) | Non-Operated (n=20) | p |
| ||||||||
Anterior Drawer Test, n (%) |
|
|
|
| ||||||||
| (-) | 18 (85,7) | 9 (45,0) | 0,004a |
| |||||||
| (1+) | 3 (14,3) | 3 (15,0) |
| ||||||||
| (2+.) | 0 | 8 (40,0) |
| ||||||||
Anterior Drawer Test Group, n (%) |
|
|
|
| ||||||||
| Negative | 18 (85,7) | 9 (45,0) | 0,016b |
| |||||||
| Positive | 3 (14,3) | 11 (55,0) |
| ||||||||
Slipping Feeling, n (%) |
|
|
|
| ||||||||
| (-) | 16 (76,2) | 11 (55,0) | 0,271b |
| |||||||
| (+) | 5 (23,8) | 9 (45,0) |
| ||||||||
Injured Thigh Diameter (cm), ±S | 59,50±6,18 | 57,80±5,47 | 0,433 |
| ||||||||
Healthy Thigh Diameter (cm), ±S | 60,62±6,61 | 58,12±5,45 | 0,230 |
| ||||||||
Thigh Diameter Differences (cm), median (min-max) | 1 (-1;4,5) | 0,5 (-1;1) | 0,021 |
| ||||||||
Injured Quadriceps Femoris Muscle Thickness (mm), ±S | 27,79±6,49 | 25,49±6,52 | 0,901 |
| ||||||||
Healthy Quadriceps Femoris Muscle Thickness (mm), ±S | 30,48±6,78 | 26,48±6,84 | 0,901 |
| ||||||||
Quadriceps Femoris Muscle Thickness Differences (mm), median (min-max) | 3,40 (-5,45;9,10) | -0,05 (-3,40;7,50) | 0,570 |
| ||||||||
Injured Hamstring Muscle Thickness (mm), ±S | 31,27±8,40 | 26,80±7,02 | 0,570 |
| ||||||||
Healthy Hamstring Muscle Thickness (mm), ±S | 35,04±8,23 | 26,89±7,52 | 0,324 |
| ||||||||
Hamstring Muscle Thickness Differences (mm), median (min-max) | 4,65 (-4,0;8,4) | 0,28 (-7,4;8,1) | 0,730 |
| ||||||||
Lysholm Knee Scale, median (min-max) | 90 (48-100) | 81,5 (31-100) | 0,367d |
| ||||||||
| Bad, n (%) | 2 (9,5) | 3 (15,0) | 0,737 |
| |||||||
| Moderate, n (%) | 6 (28,6) | 8 (40,0) |
| ||||||||
| Good, n (%) | 5 (23,8) | 4 (20,0) |
| ||||||||
| Perfect, n (%) | 8 (38,1) | 5 (25,0) |
| ||||||||
Distanced One-Step Jump Test, n (%) |
|
|
|
| ||||||||
| Asymmetric | 3 (14,3) | 5 (25,0) | 0,454b |
| |||||||
| Symmetric | 18 (85,7) | 15 (75,0) |
| ||||||||
Timed One-Step Jump Test, n (%) |
|
|
|
| ||||||||
| Asymmetric | 0 | 0 | ----- |
| |||||||
| Symmetric | 21 (100) | 20 (100) |
| ||||||||
ACL-QOL |
|
|
|
| ||||||||
Symptoms and Physical Complaints | 87,17 (17,17-100) | 77,66 (16,74-100) | 0,375 d | |||||||||
Work-Related Concerns | 97,61 (21,09-100) | 63,80 (0-100) | 0,011 d | |||||||||
Hobbies, Sports or Competition Participation | 56,45 (0,72-98,70) | 25,22 (0,43-100) | 0,047 d | |||||||||
Life style | 89,42 (12,75-100) | 62,59 (3,30-100) | 0,167 d | |||||||||
Social and Emotional | 71,30 (12,70-100) | 34,78 (0-96,52) | 0,020 d | |||||||||
TOTAL | 408,6 (76,6-498,7) | 277,1 (31,4-459,1) | 0,030 d | |||||||||
|
|
|
|
|
| |||||||
: Mean; S: Standard Deviation; n: Patient Number, ACL-QOL: Anterior Cruciate Ligament-Quality of Life A:Chi-Square Test; b:Fisher Exact Test; c:Student’s T Test; d:Mann-Whitney U Test |
| |||||||||||
Table 3: The Relationship Between the Anterior Cruciate Ligament Quality of Life Questionnaire and Age, Body Mass Index, Injury Duration, Tegner Score, Lysholm Knee Scale Score, and Differences in Thigh Diameter and Muscle Thickness, According to Operative Status
| Symptoms and Physical Complaints | Work-Related Concerns | Hobbies, Sports or Competition Participation | Life style | Social and Emotional | TOTAL | |
Operated (n=21) |
|
|
|
|
|
| |
| Age | -0,106 | -0,128 | -0,131 | -0,097 | -0,150 | -0,095 |
| BMI | -0,083 | -0,215 | -0,048 | 0,008 | -0,026 | -0,086 |
| Time Since Injured | -0,054 | 0,127 | -0,175 | -0,231 | -0,064 | -0,104 |
| Tegner Activity Score | 0,354 | 0,354 | 0,363 | 0,297 | 0,246 | 0,371 |
| Lysholm Knee Scale | 0,743** | 0,666** | 0,709** | 0,560** | 0,608** | 0,707** |
| Thigh Diameter Differences | 0,370 | 0,357 | 0,347 | 0,255 | 0,379 | 0,374 |
| Quadriceps Muscle Thickness Differences | 0,213 | 0,250 | 0,318 | 0,229 | 0,286 | 0,273 |
| Hamstring Muscle Thickness Differences | -0,411 | -0,200 | -0,395 | -0,207 | -0,404 | -0,397 |
Non-Operated (n=20) |
|
|
|
|
|
| |
| Age | 0,036 | 0,066 | -0,106 | -0,252 | -0,248 | -0,163 |
| BMI | 0,017 | 0,157 | 0,066 | -0,035 | 0,000 | -0,003 |
| Time Since Injured | 0,003 | -0,012 | 0,041 | -0,029 | -0,185 | -0,061 |
| Tegner Activity Score | 0,090 | 0,054 | -0,036 | 0,151 | 0,182 | 0,136 |
| Lysholm Knee Scale | 0,632** | 0,580** | 0,680** | 0,565** | 0,611** | 0,680** |
| Thigh Diameter Differences | -0,027 | -0,129 | -0,038 | -0,199 | -0,096 | -0,123 |
| Quadriceps Muscle Thickness Differences | 0,223 | -0,305 | 0,060 | 0,238 | 0,105 | 0,054 |
| Hamstring Muscle Thickness Differences | 0,396 | 0,335 | 0,198 | 0,296 | 0,314 | 0,347 |
*p<0,05; **p<0,01 | |||||||
Table 4: The Relationship Between Anterior Cruciate Ligament Quality of Life Questionnaire Score and Isometric Muscle Strength Measurements of Operated and Non-Operated Patients
OPERATED (n=21) | Symptoms and Physical Complaints | Work-Related Concerns | Hobbies, Sports or Competition Participation | Life style | Social and Emotional | TOTAL | |
Extension |
|
|
|
|
|
| |
PT (60o/sn) | Injured | 0,684** | 0,505* | 0,692** | 0,569** | 0,652** | 0,652** |
Healthy | 0,033 | -0,082 | 0,100 | 0,000 | -0,077 | 0,050 | |
PT %BW (60o/sn) | Injured | 0,818** | 0,680** | 0,665** | 0,474* | 0,709** | 0,693** |
Healthy | 0,205 | 0,091 | 0,123 | -0,062 | 0,154 | 0,171 | |
PT (240o/sn) | Injured | 0,299 | 0,157 | 0,428 | 0,403 | 0,383 | 0,364 |
Healthy | 0,025 | -0,086 | 0,167 | -0,021 | -0,001 | 0,093 | |
PT %BW (240o/sn) | Injured | 0,577** | 0,480* | 0,515* | 0,433* | 0,547* | 0,531* |
Healthy | 0,052 | -0,033 | 0,063 | -0,151 | -0,050 | 0,048 | |
TW (240o/sn) | Injured | 0,257 | 0,019 | 0,322 | 0,261 | 0,296 | 0,256 |
Healthy | -0,151 | -0,316 | -0,026 | -0,071 | -0,113 | -0,082 | |
TW %BW (240o/sn) | Injured | 0,343 | 0,089 | 0,318 | 0,248 | 0,430 | 0,286 |
Healthy | -0,047 | -0,188 | -0,157 | -0,352 | -0,144 | -0,134 | |
Flexion |
|
|
|
|
|
| |
PT (60o/sn) | Injured | 0,571** | 0,241 | 0,575** | 0,424 | 0,354 | 0,491* |
Healthy | 0,197 | -0,110 | 0,187 | 0,077 | 0,049 | 0,118 | |
PT %BW (60o/sn) | Injured | 0,653** | 0,420 | 0,455* | 0,219 | 0,340 | 0,438* |
Healthy | 0,368 | 0,126 | 0,213 | 0,030 | 0,130 | 0,219 | |
PT (240o/sn) | Injured | 0,264 | 0,077 | 0,381 | 0,403 | 0,236 | 0,290 |
Healthy | 0,101 | -0,115 | 0,162 | 0,083 | 0,031 | 0,112 | |
PT %BW (240o/sn) | Injured | 0,467* | 0,379 | 0,404 | 0,355 | 0,335 | 0,393 |
Healthy | 0,214 | 0,061 | 0,158 | 0,024 | 0,052 | 0,169 | |
TW (240o/sn) | Injured | 0,427 | 0,083 | 0,397 | 0,198 | 0,309 | 0,329 |
Healthy | 0,056 | -0,241 | 0,091 | -0,032 | -0,026 | 0,030 | |
TW %BW (240o/sn) | Injured | 0,597** | 0,325 | 0,395 | 0,134 | 0,367 | 0,401 |
Healthy | 0,222 | 0,009 | 0,087 | -0,055 | -0,001 | 0,099 | |
Hamstring/ Quadriceps (60o/sn) | Injured | -0,069 | -0,210 | -0,194 | -0,307 | -0,368 | -0,262 |
Healthy | 0,371 | 0,092 | 0,201 | 0,170 | 0,142 | 0,195 | |
Hamstring/ Quadriceps (240o/sn) | Injured | 0,091 | 0,060 | 0,034 | 0,033 | -0,140 | 0,000 |
Healthy | 0,303 | 0,107 | 0,177 | 0,229 | 0,187 | 0,203 | |
NON-OPERATED (n=20) |
|
|
|
|
|
| |
Extension |
|
|
|
|
|
| |
PT (60o/sn) | Injured | 0,274 | 0,296 | 0,298 | 0,320 | 0,272 | 0,316 |
Healthy | -0,136 | -0,105 | -0,183 | -0,073 | -0,048 | -0,126 | |
PT %BW (60o/sn) | Injured | 0,320 | 0,290 | 0,280 | 0,241 | 0,229 | 0,356 |
Healthy | 0,029 | -0,035 | -0,014 | 0,023 | 0,034 | 0,076 | |
PT (240o/sn) | Injured | 0,647** | 0,487* | 0,346 | 0,361 | 0,338 | 0,498* |
Healthy | 0,183 | -0,037 | -0,047 | 0,063 | -0,001 | -0,014 | |
PT %BW (240o/sn) | Injured | 0,546* | 0,358 | 0,320 | 0,341 | 0,303 | 0,451* |
Healthy | 0,169 | -0,148 | -0,142 | -0,038 | -0,147 | -0,081 | |
TW (240o/sn) | Injured | 0,593** | 0,343 | 0,332 | 0,547* | 0,436 | 0,477* |
Healthy | 0,380 | 0,108 | 0,236 | 0,314 | 0,305 | 0,274 | |
TW %BW (240o/sn) | Injured | 0,705** | 0,388 | 0,398 | 0,561* | 0,487* | 0,584** |
Healthy | 0,571** | 0,213 | 0,330 | 0,417 | 0,405 | 0,462* | |
Flexion |
|
|
|
|
|
| |
PT (60o/sn) | Injured | 0,501* | 0,237 | 0,287 | 0,348 | 0,209 | 0,332 |
Healthy | -0,058 | -0,183 | -0,321 | -0,155 | -0,248 | -0,255 | |
PT %BW (60o/sn) | Injured | 0,721** | 0,357 | 0,487* | 0,440 | 0,398 | 0,573** |
Healthy | 0,220 | -0,167 | -0,044 | 0,011 | -0,004 | 0,020 | |
PT (240o/sn) | Injured | 0,500* | 0,274 | 0,387 | 0,288 | 0,346 | 0,439 |
Healthy | 0,066 | -0,029 | -0,176 | -0,020 | -0,149 | -0,126 | |
PT %BW (240o/sn) | Injured | 0,523* | 0,227 | 0,380 | 0,316 | 0,348 | 0,452* |
Healthy | 0,317 | 0,113 | 0,023 | 0,138 | 0,005 | 0,121 | |
TW (240o/sn) | Injured | 0,699** | 0,408 | 0,492* | 0,537* | 0,426 | 0,565** |
Healthy | 0,287 | 0,080 | -0,085 | 0,093 | -0,059 | 0,035 | |
TW %BW (240o/sn) | Injured | 0,760** | 0,408 | 0,507* | 0,513* | 0,442 | 0,611** |
Healthy | 0,528* | 0,098 | 0,177 | 0,281 | 0,165 | 0,283 | |
Hamstring/ Quadriceps (60o/sn) | Injured | 0,223 | -0,142 | -0,084 | -0,096 | -0,140 | -0,065 |
Healthy | -0,064 | -0,104 | -0,306 | -0,223 | -0,305 | -0,271 | |
Hamstring/ Quadriceps (240o/sn) | Injured | 0,096 | -0,018 | 0,289 | 0,247 | 0,220 | 0,195 |
Healthy | 0,098 | 0,161 | -0,009 | 0,038 | -0,116 | 0,005 | |
*p<0,05; **p<0,01 | |||||||
Figure Legends
Figure 1: Ultrasonographic Measurement Location of M. Rectus Femoris and Vastus Intermedius
Figure 2: Ultrasonographic Measurement Location of Hamstring Muscles
Figure 3: An Image of the Isokinetic Evaluation
About the authors
Pınar Arda Bulut
Email: pinarda88@hotmail.com
ORCID iD: 0000-0002-1770-2258
Aylin Ayyıldız
Author for correspondence.
Email: aylin.mrt93@gmail.com
ORCID iD: 0000-0002-7163-8234
Турция
Selda Çiftci İnceoğlu
Email: seldavd@gmail.com
ORCID iD: 0000-0002-0387-3558
Figen Yılmaz
Email: figenyilmaz@yahoo.com
ORCID iD: 0000-0002-0825-5169
Türker Şahinkaya
Email: turkerss@gmail.com
ORCID iD: 0000-0003-1466-381X
Osman Tuğrul Eren
Email: tugruleren@hotmail.com
ORCID iD: 0000-0002-7675-9297
Banu Kuran
Email: banukuran@gmail.com
ORCID iD: 0000-0003-2273-1018
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Supplementary files



