Rehabilitation modalities in ankylosing spondylitis: orthopaedic perspectives on function, bone health, and surgical safety.

Ankylosing Spondylitis (AS) is a chronic inflammatory disorder primarily affecting the axial skeleton, leading to progressive spinal fusion, kyphotic deformity, and heightened fracture risk. This review synthesises current evidence on physical rehabilitation strategies essential for orthopaedic management across disease stages. Key assessment tools-Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI), and Bath Ankylosing Spondylitis Metrology Index (BASMI)-enable multidimensional evaluation of disease activity, functional capacity, and spinal mobility. Conservative rehabilitation, particularly land-based exercise (LBE) and aquatic therapy, demonstrates moderate efficacy in improving mobility and function, with aquatic modalities offering superior pain relief and psychological benefits. Supervised physical therapy outperforms unsupervised programs, leading to greater adherence and better clinical outcomes. Exercise also contributes to bone mineral density (BMD) enhancement, especially at the femoral neck and hip, with mind-body and resistance training ranking highest in efficacy. However, current protocols have a limited impact on pathological bone formation (ankylosis), underscoring the need for optimised mechanical loading strategies. Telerehabilitation offers accessibility benefits but may lack the fidelity of in-person supervision, especially for complex biomechanical corrections. Perioperative rehabilitation is critical in surgical candidates, with prehabilitation targeting metabolic optimisation and postoperative protocols tailored to protect instrumentation and restore function. Total Hip Arthroplasty (THA) requires strict adherence to positioning precautions due to spinal rigidity, and prophylaxis against heterotopic ossification is mandatory. Overall, physical rehabilitation is indispensable in mitigating orthopaedic complications, preserving mobility, and enhancing quality of life in AS patients. High-fidelity, supervised, and multimodal programs should be prioritised to maximise therapeutic outcomes and delay surgical intervention.