European Journal of Cardiovascular Medicine

Fracture healing is a highly orchestrated biological process that aims to restore the structural integrity and function of bone through successive phases of inflammation, repair, and remodeling. The outcome of this process depends on multiple mechanical and biological factors, including stability at the fracture site, vascularity, and the mechanical environment created by the fixation method [1]. Among the available techniques, intramedullary nailing (IMN) has emerged as the preferred modality for long-bone diaphyseal fractures, providing optimal axial alignment, rotational stability, and early functional recovery [1,2].

Reamed and unreamed IM nailing techniques have been widely investigated for their influence on union rate, callus formation, and time to healing. Reamed nailing, by restoring the medullary canal and improving endosteal contact, has been shown to enhance the biological milieu for bone regeneration without significantly increasing complications [3]. Large multicenter trials, such as the SPRINT study, have confirmed that the success of IM nailing depends not only on implant design but also on patient-specific and fracture-related prognostic factors, reinforcing the need for systematic clinical and radiological follow-up [3].

Accurate assessment of fracture healing remains a persistent challenge in orthopaedic practice. Radiographic evaluation using standardized scoring systems, such as the Radiographic Union Score, provides a reproducible framework for quantifying callus formation and cortical bridging [4]. However, radiological consolidation does not always coincide with complete clinical recovery, and early healing may be better detected by adjunctive imaging modalities, including ultrasound, which can identify callus formation before it becomes radiographically evident [5].

Given these considerations, this prospective observational study was designed to evaluate the correlation between clinical and radiological parameters of fracture healing in patients with long-bone fractures managed by intramedullary nailing, and to determine the rate and quality of union using standardized criteria.

The present prospective observational study was undertaken to evaluate the correlation between clinical and radiological indicators of fracture healing in patients with long bone fractures treated by intramedullary nailing, and to analyze associated functional outcomes and postoperative complications

Fracture healing is a highly orchestrated biological process that aims to restore the structural integrity and function of bone through successive phases of inflammation, repair, and remodeling. The outcome of this process depends on multiple mechanical and biological factors, including stability at the fracture site, vascularity, and the mechanical environment created by the fixation method [1]. Among the available techniques, intramedullary nailing (IMN) has emerged as the preferred modality for long-bone diaphyseal fractures, providing optimal axial alignment, rotational stability, and early functional recovery [1,2].

Reamed and unreamed IM nailing techniques have been widely investigated for their influence on union rate, callus formation, and time to healing. Reamed nailing, by restoring the medullary canal and improving endosteal contact, has been shown to enhance the biological milieu for bone regeneration without significantly increasing complications [3]. Large multicenter trials, such as the SPRINT study, have confirmed that the success of IM nailing depends not only on implant design but also on patient-specific and fracture-related prognostic factors, reinforcing the need for systematic clinical and radiological follow-up [3].

Accurate assessment of fracture healing remains a persistent challenge in orthopaedic practice. Radiographic evaluation using standardized scoring systems, such as the Radiographic Union Score, provides a reproducible framework for quantifying callus formation and cortical bridging [4]. However, radiological consolidation does not always coincide with complete clinical recovery, and early healing may be better detected by adjunctive imaging modalities, including ultrasound, which can identify callus formation before it becomes radiographically evident [5].

Given these considerations, this prospective observational study was designed to evaluate the correlation between clinical and radiological parameters of fracture healing in patients with long-bone fractures managed by intramedullary nailing, and to determine the rate and quality of union using standardized criteria.

The present prospective observational study was undertaken to evaluate the correlation between clinical and radiological indicators of fracture healing in patients with long bone fractures treated by intramedullary nailing, and to analyze associated functional outcomes and postoperative complications

A total of 50 patients with long bone fractures treated using intramedullary nailing were evaluated prospectively for clinical and radiological evidence of fracture healing over a period of 24 weeks. The findings are summarized in Tables 1–4.

Demographic Profile

The age of participants ranged from 18 to 65 years, with a mean of 37.6 ± 11.2 years. The majority (28%) belonged to the 31–40-year age group. Males (68%) predominated over females (32%), reflecting greater exposure to outdoor activities and vehicular trauma. Road traffic accidents were the most frequent cause of injury (64%), followed by accidental falls (28%) and other causes such as sports or industrial trauma (8%) (Table 1).

Table 1. Demographic Profile of Patients (n = 50)

Fracture Characteristics

The tibia was involved in 56% of cases and the femur in 44%. According to the AO classification, simple fractures (type A) accounted for 60% of cases, followed by wedge (B) and complex (C) patterns comprising 28% and 12%, respectively. The right limb was affected slightly more often (58%) than the left (42%) (Table 2).

Table 2. Fracture Characteristics

Clinical and Radiological Healing

Progressive improvement was noted across follow-up visits. At 6 weeks, early callus formation was evident radiographically in 48% of patients, while only 20% demonstrated clinical union. By 12 weeks, clinical and radiological union were observed in 70% and 76% of cases, respectively. Near-complete union was achieved in most patients by 18 weeks, and 47 patients (94%) demonstrated both clinical and radiological union at 24 weeks. The mean time to union was 17.2 ± 3.6 weeks, with a strong positive correlation between clinical and radiological healing (r = 0.84, p < 0.001) (Table 3).

Table 3. Clinical and Radiological Progress of Fracture Healing

Functional Outcome and Complications

Based on Johner and Wruhs criteria, excellent to good outcomes were achieved in 42 patients (84%), while 6 (12%) had fair and 2 (4%) had poor results. Minor complications were reported in 8 patients (16%), the most common being superficial infection (6%), delayed union (6%), limb shortening < 1 cm (4%), and knee stiffness (4%). All complications were managed conservatively without implant failure (Table 4).

Table 4. Functional Outcome and Complications

This prospective observational study analyzed the temporal relationship between clinical and radiological healing in long-bone fractures managed with intramedullary nailing (IMN). A 94 % union rate was achieved within 24 weeks, with a strong positive correlation (r = 0.84) between clinical and radiographic indicators of healing. These findings confirm that IMN provides rigid fixation, permits early mobilization, and ensures predictable fracture union in properly selected diaphyseal injuries [6].

Correlation Between Clinical and Radiological Union

Radiographic callus formation was consistently observed earlier than the complete resolution of clinical tenderness, which became congruent by 18–24 weeks. This temporal disparity reflects the biological sequence of bone repair radiological callus precedes full mechanical stability and pain-free function. Our results align with the variability in fracture-healing assessment reported by Corrales et al. [7], who emphasized that no single parameter accurately defines union, underscoring the value of combined clinical and radiographic evaluation. The observed correlation coefficient (r = 0.84) corroborates the reproducibility of integrated assessment protocols in determining fracture consolidation.

Union Rate and Healing Time

The mean time to union in our series (17.2 ± 3.6 weeks) parallels previous multicentric evidence supporting IM nailing as the optimal strategy for fracture stabilization and biological repair. Haonga et al. [6] demonstrated, in a randomized trial comparing IMN and external fixation for open tibial fractures, that IMN achieved significantly higher union rates and fewer complications, reaffirming its role in promoting early callus maturation and durable healing. The slightly prolonged union time in tibial fractures in our cohort may be attributed to limited soft-tissue coverage and reduced vascularity typical of the subcutaneous tibial surface.

Functional Outcome

Using the Johner and Wruhs criteria, 84 % of our patients achieved excellent-to-good results. Early physiotherapy, optimal implant stability, and progressive weight-bearing were instrumental in functional recovery. Comparable functional improvements following different IMN approaches have been reported by Jones et al. [8], who found that both retropatellar and infrapatellar routes yielded equivalent radiologic consolidation and patient-reported outcomes, highlighting the versatility of intramedullary techniques in long-bone reconstruction.

Complications

The overall complication rate in the present study was low (16 %), comprising minor issues such as superficial infection, knee stiffness, and mild limb shortening. No implant failures or non-unions were encountered. These outcomes are comparable to the low infection rates and high union rates (> 90 %) reported by Haonga et al. [6]. Our results further confirm that meticulous surgical technique, adequate reaming, and adherence to aseptic principles minimize postoperative morbidity.

Interpretation and Broader Context

Assessment of fracture healing remains inherently variable and subject to interobserver differences, as noted by Corrales et al. [7]. Reliable outcome measurement requires integrating clinical findings with standardized radiological scales, ideally supplemented by advanced imaging modalities. However, not all imaging or analytical techniques translate meaningfully to clinical orthopaedics. For instance, investigations from unrelated fields such as Abbiss et al. [10] on athletic performance metrics and Balthazar et al. [11] on radiologic reporting accuracy demonstrate that methodological consistency and interpretive objectivity are essential for meaningful data translation, a principle equally relevant to fracture-healing research.

Clinical Implications

The findings highlight the importance of integrated clinical–radiological evaluation in guiding postoperative management. Reliance on either modality alone may lead to premature or delayed weight-bearing decisions. Routine follow-up at standardized intervals allows early detection of delayed union and enables timely interventions such as dynamization or biological augmentation. Furthermore, early physiotherapy and progressive loading were associated with improved functional scores in our cohort.

Limitations

This study was limited by its modest sample size and single-center design, which may affect generalizability. The absence of a comparative group (such as plating or external fixation) precluded direct evaluation of alternative techniques. Advanced scoring systems like the Radiographic Union Scale for Tibia (RUST) were not employed, which could have provided a more standardized radiological assessment. Nevertheless, the prospective design and consistent follow-up strengthen the internal validity of findings.

This prospective study establishes that intramedullary nailing ensures reliable fracture stabilization and predictable union in long bones, with a strong correlation between clinical recovery and radiological consolidation. The high union rate (94%) and excellent functional outcomes observed confirm the biomechanical and biological advantages of intramedullary fixation in promoting secondary bone healing through callus formation. Minimal complications and favorable rehabilitation profiles further support its continued use as the standard treatment for diaphyseal fractures of the femur and tibia. Integrating serial clinical and radiological assessment provides a comprehensive and objective approach to monitor healing and to guide progressive mobilization in postoperative orthopedic care.

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