Patellar fractures account for approximately 1% of all skeletal injuries and can severely disrupt the integrity of the knee’s extensor mechanism, leading to impaired mobility and function if not appropriately treated¹. As the largest sesamoid bone in the human body, the patella acts as a fulcrum to enhance the function of quadriceps mechanism thus, playing a key role in knee biomechanics and load transmission². Restoration of the anatomical structure and function of the patella is crucial for achieving favourable postoperative outcomes, particularly in high-demand individuals. Among the various fracture types, comminuted fractures, especially those classified as AO type 34 C2 and C3, present unique challenges in terms of fragment stability, articular congruity, and soft tissue preservation³. These injuries are commonly associated with high-energy trauma, such as dashboard injuries, falls from height, and direct blows to the knee⁴. The AO/OTA classification serves as a standard framework for describing fracture patterns, with type C2 and C3 indicating multifragmentary intra-articular fractures with severe disruption of patellar architecture⁵. Tension band wiring (TBW) has traditionally been used for simple transverse patella fractures (AO type C1). It converts the tensile forces on the anterior surface into compressive forces at the articular surface during knee flexion⁶. However, the conventional TBW technique is inadequate in comminuted patterns where multiple small fragments are present, leading to poor fixation and risk of failure⁷. To overcome this limitation, modified or multiple tension band wiring techniques have been developed. These involve the use of multiple parallel or crossed K-wires along with stainless steel loops, providing improved fragment control and enabling early rehabilitation⁸. Several studies have explored alternative methods including cerclage wiring, screw fixation, and mesh plating, but each method has its limitations, particularly in achieving stable fixation in fragmented fractures⁹. In contrast, multiple TBW techniques offer the advantages of preserving bone stock, achieving adequate stability, and facilitating early mobilization—critical factors in preventing stiffness, extensor lag, and muscle atrophy¹⁰. While patellectomy was previously advocated for severely comminuted fractures, it is now largely discouraged due to consistently poorer outcomes, especially regarding quadriceps strength and knee extension power¹¹. With increasing emphasis on anatomical preservation and functional recovery, multiple TBW techniques are being re-evaluated for their efficacy in managing complex patellar fractures¹². The Böstman clinical scoring system, a validated outcome measure for patellar fracture recovery, combines objective (range of motion, work capacity, walking ability) and subjective (pain, atrophy, stiffness) parameters to assess knee function¹³. Despite its wide acceptance, limited prospective data exist on its application in AO 34 C2/C3 fractures treated with multiple TBW in Indian tertiary care settings. Hence, this study was designed to evaluate the functional outcome of comminuted patella fractures (AO type 34 C2 & C3) managed by multiple tension band wiring. The objective was to assess post-operative recovery using Böstman scores over 6 months and to determine the safety, stability, and rehabilitation potential of this surgical technique in a real-world clinical scenario.

Study Design This was a prospective-retrospective observational study conducted to evaluate the functional outcomes of comminuted patellar fractures classified as AO type 34 C2 and C3, managed surgically by multiple tension band wiring (TBW). The study aimed to assess post-operative recovery using clinical and functional outcome measures over a 6-month period following surgical fixation. Study Setting The study was conducted at the Department of Orthopaedics, Pt. J.N.M. Medical College & associated Dr. B.R.A.M. Hospital, Raipur, Chhattisgarh, a tertiary-level healthcare institution catering to a wide Orthopaedic trauma population. Study Duration The study was carried out over a 24-month period from March 2023 to March 2025. Study Population All patients presenting between 20- 60yrs of age with closed comminuted patella fractures classified as AO type 34 C2 or C3, and managed with multiple tension band wiring, were considered eligible during the study period. And no other injury in ipsilateral limb. Methodology All patients with suspected comminuted displaced patella fractures (<20 days old) were clinically evaluated. Baseline demographic data including age, sex, occupation, and mechanism of injury were recorded. Detailed history was obtained including the nature of trauma (e.g., fall, dashboard injury, RTA) and functional complaints. Radiological confirmation was done using anteroposterior and lateral knee radiographs, and fractures were classified as per AO/OTA system. Once eligibility was confirmed, informed written consent was obtained. Pre-anaesthesia evaluation, surgical counselling, and routine blood work were conducted. Patients were taken for surgery under spinal anaesthesia following proper sterile preparation. Surgical Technique The patients were placed in a supine position with a pneumatic thigh tourniquet applied to minimize intraoperative bleeding. The affected knee was slightly flexed and elevated using a sandbag or towel to improve surgical exposure. A midline longitudinal incision (8–10 cm) was made over the anterior aspect of the knee. Fracture hematoma was evacuated and all fragments were exposed. Fracture fixation was done using 1.8 mm or 2 mm K-wires, along with 16 or 18 SWG stainless steel wire configured as multiple tension bands. The construct aimed to stabilize all major fragments while preserving the patella’s articular congruity. Stability was checked intraoperatively under C-arm. Figure 1 Postoperative Protocol All patients were monitored for vitals and neurovascular status in the immediate post-operative period. Dressing was done on postoperative day 3 and day 5, and patients were discharged if the wound was dry and stable. The knee was immobilized in a cylindrical slab in 5°–10° flexion for 10 days to ensure soft tissue healing. Quadriceps isometric exercises were initiated from day 1 postoperatively. Passive knee range of motion (ROM) was started from postoperative day 10–12, and active ROM was encouraged at the time of suture removal (around 2 weeks), depending on patient tolerance. Patients were followed up at 6 weeks, 3 months, and 6 months. [Figure 2] Functional Outcome Assessment Outcomes were evaluated using the Böstman Clinical Grading Score, which includes parameters such as pain, range of motion, atrophy, walking capacity, work capability, and complications¹⁴. Range of Motion (ROM) was separately recorded at 6 months using a goniometer, and classified as full or restricted. Figure 1: various steps involved in the Surgical Technique [ Painting & Draping, Midline longitudinal incision, Fracture fragments after evacuation of hematoma, Wire is tightened using T-handle,] Figure 2: X-ray showing preoperative [ A, B] and 6-month follow up [C, D] of patient with clinical picture[E] Findings: The majority of patients were between 20–30 years and 41–50 years (each contributing 30.8%). Patients over 50 years comprised 23.1%, while the smallest group (15.4%) were in the 31–40 age range. This suggests a higher incidence in young and middle-aged adults, likely due to increased activity levels and trauma exposure. Figure 3

A total of 13 patients with comminuted patella fractures (AO type 34 C2 and C3) were enrolled in the study and underwent surgical fixation using the multiple tension band wiring technique. The findings from the core data tables are summarized below: Table 1: Age Distribution Among Study Population Age Range No. of Patients Percentage (%) 20–30 years 4 30.8 31–40 years 2 15.4 41–50 years 4 30.8 >50 years 3 23.1 Total 13 100 Findings: The majority of patients were between 20–30 years and 41–50 years (each contributing 30.8%). Patients over 50 years comprised 23.1%, while the smallest group (15.4%) were in the 31–40 age range. This suggests a higher incidence in young and middle-aged adults, likely due to increased activity levels and trauma exposure. Figure 3 Figure 3: Age distribution Table 2: Distribution of Complications Complication Frequency Percentage (%) Nil 9 64.3 Surgical Site Infection (SSI) 1 7.1 Implant Irritation 3 21.4 Hardware Migration 0 0 Knee Stiffness 1 7.1 Non-union/Delayed Union 0 0 Loss of Reduction 0 0 Total 14* 100 (*Total exceeds 13 due to multiple complications in a few cases.) Findings: Most patients (64.3%) had an uneventful recovery. Minor complications included implant irritation in 21.4% and surgical site infection and knee stiffness in 7.1% each. There were no major complications like hardware migration, loss of reduction, or non-union, indicating favorable surgical outcomes and implant stability. Figure 4 Figure 4: Distribution of Complications Table 3: Functional Outcome Grade Outcome Grade Frequency Percentage (%) Excellent 5 38.46 Good 7 53.84 Unsatisfactory 1 7.69 Total 13 100 Findings: At final follow-up (6 months), 92.3% of patients achieved either excellent (38.46%) or good (53.84%) functional outcomes. Only one patient (7.69%) had an unsatisfactory result, highlighting the efficacy of the multiple TBW technique in restoring function in comminuted fractures. Figure 5 Figure 5: Functional Outcome Grade Table 4: Mean Böstman Score Over Time Duration Mean ± SD Min–Max F-value p-value 6 Weeks 14.23 ± 2.68 8–18 3 Months 20.53 ± 3.57 12–26 6 Months 25.92 ± 3.37 16–29 42.57 <0.001 Findings: There was a statistically significant improvement in Böstman scores from 6 weeks to 3 months and from 3 months to 6 months (p < 0.001). The mean score improved from 14.23 at 6 weeks to 25.92 at 6 months, indicating progressive functional recovery. This trend underscores the effectiveness of early mobilization and stable fixation in improving patient outcomes. Figure 6 Figure 6: Mean Böstman Score Over Time

Comminuted fractures of the patella, especially those classified as AO type 34 C2 and C3, pose significant challenges to Orthopaedic surgeons due to the complexity of fragment stabilization, disruption of the extensor mechanism, and difficulty in restoring the congruent articular surface of the patellofemoral joint. In the present study, multiple tension band wiring (TBW) was employed in 13 patients, and the functional outcomes were evaluated using the Böstman scoring system over a 6-month period. The mean age of the study population was consistent with other Indian studies reporting similar fractures among adults in the active age group, primarily 20–50 years, where road traffic accidents and falls are the common mechanisms of trauma [1,2]. Males predominated (84.6%), aligning with existing literature indicating higher exposure of males to high-velocity trauma and occupational hazards [3]. The primary aim of surgical management in patellar fractures is to achieve stable fixation that allows early mobilization and rehabilitation without compromising the extensor mechanism. Although standard tension band wiring using two parallel K-wires and stainless steel wire remains the conventional approach for transverse fractures [4], it is often inadequate in multifragmentary cases. This study employed multiple K-wires and tension loops, enabling fixation of both polar fragments and central comminution. Such modifications have been supported in biomechanical studies, which report improved stability and load distribution with multiple configurations [5,6]. In the current study, functional outcomes were promising, with 92.3% of patients achieving either good or excellent results by 6 months postoperatively. The mean Böstman score improved significantly across all three follow-ups—14.23 at 6 weeks, 20.53 at 3 months, and 25.92 at 6 months (p < 0.001). These findings are comparable to those reported by Kastelec and Veselko, who observed a similar upward trend in knee function using comparable fixation methods in comminuted patellar fractures [7]. The complication rate in this study was low, with only one case each of surgical site infection and stiffness (7.1%) and three cases (21.4%) of implant irritation, which is consistent with global studies reporting implant-related discomfort as the most frequent postoperative issue [8,9]. No cases of hardware migration, non-union, or loss of reduction were recorded, highlighting the biomechanical adequacy and construct stability of the multiple TBW method. In comparison, studies using partial patellectomy in severely comminuted cases have reported extensor lag and reduced quadriceps strength in up to 25–30% of cases, making bone-preserving techniques more favorable [10]. One of the major advantages of the TBW technique employed here was the early initiation of quadriceps exercises and passive range of motion, which is crucial in preventing knee stiffness and muscle wasting. By initiating motion within 8–10 days, patients demonstrated significant improvement in flexion range and walking ability by 6 weeks. This early mobilization protocol is supported by previous clinical trials indicating that early ROM post-fixation correlates with better long-term functional scores and lower incidence of adhesions [11,12]. While this study adds to the limited body of literature on Indian patients with AO 34 C2/C3 fractures, it has certain limitations. The small sample size (n=13) may restrict the generalizability of findings. Additionally, the absence of a control group treated with alternative fixation methods (e.g., mesh plating or patellectomy) limits comparative analysis. Despite these constraints, the prospective nature of the study and standardized use of validated outcome measures (Böstman score) enhance its internal validity. Emerging fixation options such as cannulated screws, titanium cables, and mesh plates offer alternative strategies, but their cost and availability in resource-limited settings remain a concern [13]. In contrast, multiple TBW offers a cost-effective, reproducible technique using easily available implants, making it highly suitable for low- to middle-income countries. Overall, the results of this study are encouraging and support the use of multiple tension band wiring for managing comminuted patella fractures with articular involvement. The technique ensures adequate fragment stability, enables early rehabilitation, and results in favorable short-term functional outcomes with minimal complications.

The present study demonstrates that multiple tension band wiring is a safe, effective, and low-cost technique for the management of comminuted patellar fractures classified as AO type 34 C2 and C3. With stable fixation and early mobilization, the majority of patients achieved good to excellent functional outcomes as measured by the Böstman score. The low complication rate and high recovery scores validate the use of this technique, especially in resource-limited Orthopaedic settings. Further randomized trials with larger sample sizes and longer follow-up are warranted to establish its superiority over alternative fixation methods.

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