Avulsion knee fractures involving the anterior cruciate ligament (ACL) are a common injury, especially amongst the young, active population participating in sports and high-velocity pursuits.[1-3] These injuries result in a tear of the ACL at the femur or tibia that frequently requires a surgical repair to repair the knee and restore stability. Additionally, the management for avulsion of the ACL is important, because a poorly or late treated collateral lesion leads to knee instability and risk of osteoarthritis, and functional results. Aim The goal of treatment of a fracture group being those of the APfx, is to obtain a stable and functional joint and the gold standard to reach this, is surgical fixation.[4-5] Many investigations have so far confirmed the efficacy of arthroscopic fixation procedures at restoring knee function and stability, showing notably clinical scores, range of movement (ROM) and stability postoperatively.[7-8] The purpose of this study is to analyze the postoperative functional results, the range of motion, the stability, and the complications after surgical treatment of avulsion fractures of the ACL. The data gained from this study will aid in the understanding of recovery trajectory and the strong predictors for recovery and beneficial impact of surgical intervention on patient outcome

In the present study, 50 patients treated with surgery for anterior cruciate ligament (ACL) avulsion fractures were included. All the patients were evaluated with clinical and functional results such as, knee stability, range of motion (ROM) and postoperative complications. The enrollment criteria of the study were adult patients diagnosed with ACL avulsion fracture receiving surgical treatment of arthroscopic fixations. The exclusion criteria were patients with previous knee operations, serious comorbidities and insufficient follow-up informations.

Functional results were determined by IKDC score (which evaluates overall knee function) and Lysholm Knee Score (which is frequently applied for assessment of knee function status after ACL injury). The ROM was evaluated in degrees at different time periods (14 days, 1 month, 3 months, 6 months, and 1 year). Knee stability was evaluated by measuring the amount of anterior-posterior tibial translation using the KT-1000 arthrometer. These clinical values which were measured from different perspectives were followed prospectively in different intervals, to estimate recovery status and progression levels. Operation time was also noted, dividing the operations into two groups; 30-60 min and 60-90 min. Recovery end points such as time to weight bearing and time to baseline activity status were also registered. post-operative complications were recorded such as cartilage lesions, arthritis, instability, fractures, infection.

Data was recorded both preoperatively and postoperatively and they were all followed up at 14 days, 1 month, 3 months, 6 months and 1 year. Statistical analysis was performed with the purpose of measuring the significance of the development of the scores and ROM over time, and to determine the presence of any complications. The statistical tests were performed and p less than 0.05 were considered significant.

Table 1: Demographic Information of Patients

The average age of the patients was 29.54±8.93 years, which means the majority of the patients with ACL avulsion fractures were in adult age, and age distribution was relatively even in different age groups. With respect to gender, there were 39 men (78%) and 11 women (22%), indicating that ACL injuries have a male preponderance, which was consistent with the greater frequency of occurrence of these fractures in males because high-impact sports and activities are more common in their higher percentage. In relation to the type of trauma, 54% were sports, 38% caused by RTA, and 8% corres p ond e d to dan c e (Table 4), emphasizing the importance of sports activities for the occurrence of acl injuries. With regard to fracture laterality, 29 (58%) and 21 (42%) patients sustained fractures of the right and left knee, respectively (Table 1), demonstrating slight right sided prominence. This demographic data is important to know the patient population and to put the results of the study into perspective.

Table 2: Distribution of Patients by Functional Outcome (IKDC Score)

After 14 days of follow-up, none of the patients was categorized as Grade A (Excellent), and most (48%) were in Grade C (Fair). There was a significant change in functional results over the following months. At 1 month, 2% of patients were in Grade A and 18% were in Grade B (Good). The proportion of patients classified into Grade A and Grade B increased at 3 months (4% in Grade A; 22% in Grade B) and 6 months after the follow-up (4% in Grade A; 26% in Grade B), respectively, which indicated that the knee-function was significantly improved.

Figure 1: Functional Improvement Over Time (IKDC Score)

One year after surgery, 24% of patients had a Grade A score, with merely 16% remaining in Grade B, none of the patients were Grade C, indicating that the functional recovery over time was very impressive. This data reveals both the incremental return of knee function and the efficacy of the surgical treatment in returning knee stability and the ability to walk.

Table 3: Lysholm Knee Score Distribution Post-Surgery

On the 14th day of follow-up, most patients had a Poor (50%) or Excellent (40%) outcome, and only a few patients were considered to be in the Fair category (10%). With the passage of time, the knee function had improved substantially. The corresponding figures at 1 month were 38% of patients in the Poor category, 22% Fair, and 40% Excellent. Poor declin ed to 26%, while Excellent increased to 46% at 3 months. At 6-month follow-up, most patients had improved markedly, 52% with Excellent scores and only 10% remaining with scores of Poor

Figure 2: Lysholm Knee Score Improvement Over Time

At 1-year follow-up 78% of patients achieved Excellent ROM, indicating marked improvement in knee function following surgery. Table The degrees of functional recovery into knee mobility and stability over time, indicating the effectiveness of the surgical treatment in the recovery of the knee function.

Table 4: Range of Motion (ROM) in Patients Post-Operatively

The average ROM at 14 days of follow-up was 23.27° with a 3.65 standard deviation. The ROM improved throughout the recovery. At 1 month the average ROM was 75.23° (SD = 4.5), and at 3 months the average ROM was 105.53° (SD = 3.35). RESULTS At the 6-month follow-up, the average ROM was 136.96° (SD 4.36), close to full extension and flexion. ROM was similar at 1 year and was 136.1° (SD = 3.35), the difference being almost negligible, indicating near full recovery of the knee.

Figure 3: Range of Motion (ROM) Progression

The mean ROM (degrees) is plotted per follow-up period in the line graph, indicating a clear increase over time after the operation. From a mean of 23.27° at 14 days, patients improved significantly to 136.96° at 6 months follow up, to 136.1° at 1 year, with almost full ROM. The shaded area surrounding the line is the standard deviation (SD) at each time point, which represents the ROM variability of patients. As follow-up time increase, the standard deviation decreases, which indicates that there is more uniform recovery across the patient population.

Table 4: Complications Observed in Patients.

The table also shows that 2 patients (4%) had cartilage injuries, and 1 patient (2%) had osteoarthritis. Specifically, there were 0% incidences of instability, fractures, and infection, respectively, suggesting a relatively low rate of severe complications. These results demonstrate that, although there was a relatively high rate of relatively minor complications such as cartilage damage and osteoarthritis, the occurrence of adverse events following surgery for ACL avulsion fractures was low in this series.

Table 5: Surgical Procedure Time and Recovery Time

With regard to operation time, most (56%) operations were finished within 30-60 minutes, and 44% were within 60-90 minutes. This time frame is indicative of good results following surgery for ACL avulsion fractures. With respect to recovery milestones, the average time to return to baseline was 30 days, a practical measure of recovery for most patients to complete performing the activities of daily living. Moreover, in the majority of the cases, patients achieved weight bearing capacity in a few mean days, which represents a good index of the postoperative early recovery and rehabilitation progression.

Table 6: Post-Operative Functional Improvement (KT-1000 Score)

The KT-1000 score (anterior-posterior tibial translation, a gauge for knee stability) at 1, 3, and 6 months was 1.17 (±0.58). This indicates that knee stability as evaluated by the KT-1000 demonstrated a steady pattern of recovery in the six months after surgery, with minimal variations among patients. In the 1-year follow-up the mean KT-1000 score increased slightly, to 1.28, and with a were mean standard deviation of the score reduced to 0.55, which could indicate that the knee stability kept on improving slightly and the patient outcomes were more similar as they were close to fully recover.

The purpose of this study was to evaluate functional status and stability after surgical management of avulsion fractures of the anterior cruciate ligament (ACL). The I KDC and Lysholm knee score as well as the advancement in range of motion (ROM) and stability of the knee were significantly improved according to the KT-1000 arthrometer results.

The IKDC score increased significantly over time (0% at 14 days and 24% at 1 year for Grade A patients). This score change highlights the effectiveness of surgery at improving knee function. Patients graded as B similarly achieved improvement, or attrition (reduction of B from 14 days to the end of the year led to falling C to 0%). These results are in agreement with previous evidence indicating that, in the case of complete ruptures, surgical repair is associated with superior recovery of knee function and stability, as compared to conservative treatment [9, 10].

The Lysholm knee score, alsoan important indicator of knee function, revealed similar positive trends. Fifty-percent of patients were initially rated as Poor at 14 days, with this percentage decreasing markedly over the year, to 78% of patients scoring as Excellent by 1 year. This pattern of findings is indicative of an overall trend toward full functional recovery, and is consistent with those reported in other studies of ACL repair in which early postoperative results show enhancement with progressive rehabilitation.[11]

Regarding ROM the patients gained significantly within the first 12 months of follow-up. The average range of motion at 14 days was 23.27° compared with 136.1° at 1 year, suggesting almost full recovery of knee mobility. This is similar to results of other such studies, which report fast gains in ROM at the beginning of rehabilitation for stabilization of knee function as healing progresses. A decrease in the standard deviation of ROM scores over time also supports the uniformity of recovery by patient group, less variation being observed as patients recovered to near full strength.[12-13]

The average KT-1000 score was steady 1.17 during the first 6 months, documenting that knee stability was maintained well within this period. By 1 year, the KT score had increased to 1.28, apparently consistent with some improvement in anterior-posterior tibial translation, consonant with the increased stability found in other studies where post-operative knee stability was recorded utilizing the same devices. Significantly, instability and other complications, remain low, thus testifying that the surgical procedures performed on these patients are effective. Two patients (4%) had cartilage damage and one (2%) had osteoarthritis, reflecting the low complication rates for such types of surgery.[14-15]

The operative time was also favorable since most procedures were completed within 30–60 min (56%) indicating efficiency of the surgical technique. The mean return to full weight-bearing was 14 days, and the mean return to full activity was 30 days, representing a fairly rapid functional recovery. This is consistent with other research, where weight-bearing and normal function is usually restored in the early weeks post-surg

The results of the present study indicate that surgical management of ACL avulsion fractures results in satisfactory recovery of knee function, ROM, and stability. At the end of the study duration, IKDC and Lysholm knee scores presented significant recovery, with, by 1 year, 24% of patients were graded as Grade A [A (Excellent)] and 78% achieved Excellent in the Lysholm scale. ROM increased from 23.27° and 136.1° at 14 days and 1 year respectively, and showed almost fully restored. Knee stability quantified by the KT-1000 recovered consistently over time and low complication rates, including 4% cartilage damage, and 2% osteoarthritis occurred. Surgery was also performed effectively with most procedures taking 30-60 min, and patients resuming normal activity within 30 days. In general, the results of this study show that the surgery of ACL avulsions is effective and safe, with good results and few complications.

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