Association Of Vitamin D Status With Fracture Pattern And Functional Outcome In Elderly Patients With Fragility Hip Fractures: A Prospective Observational Study.

Hip fractures constitute one of the most serious consequences of osteoporosis and age-related skeletal fragility. With increasing life expectancy, the number of older adults at risk of fragility fractures is expected to rise substantially. Apart from the immediate requirement for hospitalization and surgical management, hip fractures may result in prolonged immobility, functional dependence, postoperative complications and increased mortality.

 

The pathogenesis of fragility fractures is multifactorial. Advancing age, osteoporosis, sarcopenia, falls, impaired vision, polypharmacy, nutritional deficiencies and chronic systemic illnesses contribute to fracture risk. Vitamin D has an important role in calcium homeostasis, skeletal mineralization and neuromuscular function. Deficiency may lead to secondary hyperparathyroidism, increased bone turnover, muscle weakness and increased susceptibility to falls.

 

Vitamin D deficiency remains common in India despite abundant sunlight. Several factors including inadequate dietary intake, limited outdoor activity, ageing, reduced cutaneous vitamin D synthesis and comorbid diseases may contribute to deficiency among elderly individuals.

Patients presenting with a low-energy hip fracture provide an important opportunity for identifying underlying metabolic and medical abnormalities. However, evaluation of vitamin D status and secondary fracture risk may receive less attention during acute fracture management.

 

The present study was therefore undertaken to determine the prevalence of vitamin D deficiency among elderly patients presenting with fragility hip fractures and to examine its relationship with fracture pattern and short-term functional outcome.

 

AIM AND OBJECTIVES

Aim

To evaluate vitamin D status and its association with clinical, radiological and functional outcomes among elderly patients presenting with fragility hip fractures.

 

Primary Objective

To determine the prevalence of vitamin D deficiency among elderly patients with fragility hip fractures.

 

Secondary Objectives

1.             To evaluate the association between serum vitamin D levels and type of hip fracture.

2.             To compare functional recovery according to vitamin D status.

3.             To assess the relationship between medical comorbidities and functional outcome.

4.             To identify predictors of poor functional recovery following hip fracture.

Study Design and Setting

A prospective hospital-based observational study was conducted in the Departments of General Medicine, Orthopaedics and Radio-Diagnosis at Shri Balaji Institute of Medical Sciences, Raipur, Chhattisgarh.

 

Study Population

Patients aged 60 years or above presenting with a radiologically confirmed fragility fracture of the proximal femur were considered for inclusion.

 

Sample Size

A total of 120 patients fulfilling the eligibility criteria were included.

 

Inclusion Criteria

• Age ≥60 years.
• Low-energy fracture following fall from standing height or less.
• Femoral neck or intertrochanteric fracture confirmed radiologically.
• Availability of serum 25(OH)D measurement.
• Consent for participation and follow-up.

 

Exclusion Criteria

• High-energy trauma.
• Pathological fracture secondary to malignancy.
• Previous ipsilateral hip surgery.
• Severe chronic kidney disease requiring dialysis.
• Known metabolic bone disorders other than osteoporosis.
• Long-term treatment with medications substantially affecting bone metabolism where adequate clinical information was unavailable.
• Patients unable to complete follow-up assessment.

 

Clinical Evaluation

Demographic details, mechanism of injury, previous fractures, history of falls, smoking, alcohol consumption and medication history were recorded. Medical comorbidities including hypertension, diabetes mellitus, coronary artery disease, chronic respiratory disease and chronic kidney disease were documented.

 

Laboratory Investigations

Venous blood samples were obtained during admission for:

• Serum 25-hydroxyvitamin D
• Serum calcium
• Serum phosphorus
• Serum alkaline phosphatase
• Haemoglobin
• Serum creatinine
• Blood glucose

Vitamin D status was categorized as:

• Deficient: <20 ng/mL
• Insufficient: 20–29.9 ng/mL
• Sufficient: ≥30 ng/mL

 

Radiological Assessment

Plain radiographs of the pelvis with both hips and dedicated views of the affected hip were evaluated by the Department of Radio-Diagnosis. Fractures were broadly categorized into:

1. Femoral neck fractures
2. Intertrochanteric fractures

Additional imaging was performed whenever clinically indicated.

 

Treatment and Follow-up

Patients were managed according to fracture configuration, age, functional requirements, medical fitness and treating surgeon's clinical judgment.

Functional assessment was performed at approximately three months using the Modified Harris Hip Score (mHHS). Outcomes were categorized as:

• Excellent: ≥90
• Good: 80–89
• Fair: 70–79
• Poor: <70

 

Statistical Analysis

Data were analyzed using appropriate statistical software. Continuous variables were expressed as mean ± standard deviation and categorical variables as frequency and percentage. Student's t-test or analysis of variance was used for normally distributed continuous variables, while categorical variables were compared using the chi-square test or Fisher's exact test. Multivariable logistic regression was used to identify factors independently associated with poor functional outcome. A p-value <0.05 was considered statistically significant.

Patient Characteristics

A total of 120 patients were included. The mean age was 71.8 ± 7.9 years, ranging from 60 to 91 years. There were 68 (56.7%) women and 52 (43.3%) men.

 

Table 1. Baseline characteristics of study participants

 

Vitamin D Status

The mean serum 25(OH)D concentration was 18.7 ± 9.4 ng/mL.

Vitamin D deficiency was identified in 72 (60.0%) patients, while another 30 (25.0%) had vitamin D insufficiency. Only 18 (15.0%) had levels ≥30 ng/mL.

 

Table 2. Distribution according to vitamin D status

Vitamin D deficiency was more frequent among women than men (66.2% vs. 51.9%), although the difference did not reach statistical significance (p=0.11).

 

Vitamin D and Fracture Pattern

Among the 72 vitamin D-deficient patients, 46 (63.9%) had intertrochanteric fractures and 26 (36.1%) had femoral neck fractures.

 

Table 3. Fracture pattern according to vitamin D status

Although intertrochanteric fractures were proportionately more common among deficient patients, the association was not statistically significant.

 

FUNCTIONAL OUTCOME

At three-month follow-up, the overall mean Modified Harris Hip Score was 65.2 ± 12.9.

Patients with vitamin D deficiency demonstrated significantly poorer functional scores.

 

Table 4. Vitamin D status and three-month functional outcome

Thus, patients with vitamin D deficiency demonstrated a substantially greater frequency of poor functional recovery.

 

FACTORS ASSOCIATED WITH POOR FUNCTIONAL OUTCOME

On univariate analysis, increasing age, vitamin D deficiency, presence of multiple medical comorbidities and lower baseline haemoglobin were associated with poorer functional recovery.

After adjustment in multivariable analysis, three factors remained independently associated with poor outcome:

 

Table 5. Multivariable predictors of poor functional outcome

 

The present study demonstrates a high prevalence of inadequate vitamin D status among elderly patients presenting with fragility fractures of the hip. Eighty-five percent of patients had serum 25(OH)D levels below 30 ng/mL and 60% fulfilled the criterion for vitamin D deficiency.

 

These findings are relevant in the Indian setting, where hypovitaminosis D is frequently reported despite abundant sunlight. Ageing may further increase the risk through reduced cutaneous synthesis, decreased outdoor activity, inadequate nutrition and associated chronic illnesses.

 

The predominance of women in the present study is consistent with the recognized increase in fragility fracture risk following menopause. Reduced estrogen levels accelerate bone loss, and this effect may be compounded by inadequate vitamin D and calcium intake.

 

Intertrochanteric fractures constituted the commonest fracture pattern in the study. Although a greater proportion of vitamin D-deficient patients had intertrochanteric fractures, the difference was not statistically significant. This suggests that vitamin D deficiency should be regarded primarily as one component of the broader skeletal and neuromuscular risk profile rather than as an isolated determinant of fracture morphology.

 

An important observation was the relationship between vitamin D deficiency and functional recovery. Vitamin D-deficient patients had significantly lower three-month Modified Harris Hip Scores and a higher prevalence of poor outcome. Vitamin D influences both skeletal and muscle physiology. Deficiency may therefore potentially affect rehabilitation through muscle weakness, impaired balance and coexisting frailty.

 

Nevertheless, the relationship between vitamin D and outcomes following hip fracture remains complex. Previous studies have not uniformly demonstrated an independent relationship between vitamin D deficiency and postoperative mortality or complications. Consequently, vitamin D should not be considered in isolation when assessing prognosis.

 

Age and medical comorbidity were also independently associated with poorer functional recovery in the present study. This reinforces the importance of orthogeriatric or multidisciplinary management. Elderly fracture patients frequently have diabetes, hypertension, cardiovascular disease, anaemia, renal dysfunction and nutritional abnormalities that influence perioperative risk and rehabilitation.

 

The physician therefore has an important role in perioperative optimization and identification of secondary contributors to bone fragility, while the orthopaedic surgeon provides definitive fracture management and directs mobilization and rehabilitation. Radiological evaluation is essential for accurate fracture characterization and can additionally identify features suggestive of reduced bone quality or underlying pathology.

Hip fracture should therefore be viewed not merely as an isolated traumatic event but as a potential clinical marker of underlying osteoporosis and increased future fracture risk. Following stabilization of the acute fracture, patients should undergo appropriate evaluation for osteoporosis and secondary fracture prevention.

 

It is also important to distinguish treatment of documented deficiency or osteoporosis from indiscriminate vitamin D supplementation in otherwise healthy adults. Large randomized evidence has shown that vitamin D supplementation alone does not necessarily reduce fracture incidence among generally healthy adults without selected vitamin D deficiency or osteoporosis. Management should consequently be individualized according to nutritional status, bone health and overall fracture risk.

 

CLINICAL IMPLICATIONS

The findings support a comprehensive approach to elderly patients admitted with fragility hip fractures. In addition to surgical treatment, evaluation should include assessment of vitamin D status, calcium balance, renal function, anaemia, nutritional status, medical comorbidities, osteoporosis risk and falls.

Where clinically appropriate, secondary fracture prevention should include correction of documented vitamin D deficiency, adequate calcium intake, osteoporosis assessment and treatment, rehabilitation, muscle-strengthening measures and strategies to reduce future falls.

 

LIMITATIONS

The present study has several limitations. It was conducted at a single tertiary-care centre with a relatively modest sample size. Vitamin D was measured at a single time point, and seasonal variations were not assessed. Bone mineral density measurements were not available for every participant. Functional outcome was assessed at three months; longer follow-up would provide additional information regarding recovery, subsequent fractures and mortality. Residual confounding related to nutritional status, frailty, physical activity and socioeconomic factors is also possible.

Vitamin D deficiency is highly prevalent among elderly patients presenting with fragility hip fractures. In the present study, deficient vitamin D status was associated with poorer three-month functional recovery, while advanced age and multiple medical comorbidities were additional predictors of adverse functional outcome.

Fragility hip fracture should trigger comprehensive evaluation beyond surgical management alone. Collaboration between General Medicine, Orthopaedics and Radio-Diagnosis, together with appropriate rehabilitation and osteoporosis assessment, may facilitate identification of modifiable risk factors and improve secondary fracture-prevention strategies.

 

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