Patient presents with physical deconditioning, characterized by reduced functional capacity and decreased ability to perform activities of daily living (ADLs).  Symptoms include generalized weakness, fatigue, decreased endurance, and exertional dyspnea.  Onset is gradual and attributed to prolonged inactivity secondary to recent hospitalization for pneumonia (ICD-10 code J18.9).  Physical examination reveals decreased muscle strength (4/5 in bilateral lower extremities), limited range of motion in shoulders and hips, and reduced cardiorespiratory fitness evidenced by elevated heart rate and shortness of breath with minimal exertion.  Assessment supports a diagnosis of physical deconditioning (ICD-10 code R53.81).  Plan includes referral to physical therapy for gait training, therapeutic exercises to improve strength and endurance, and a graded exercise program to enhance functional mobility and restore independence with ADLs.  Patient education provided on the importance of regular physical activity and energy conservation techniques.  Prognosis is good with anticipated improvement in functional status following a course of physical therapy.  Follow-up scheduled in two weeks to monitor progress and adjust treatment plan as needed.  Differential diagnoses considered included debility, asthenia, and general weakness, but were ruled out based on clinical presentation and history of recent illness and immobility.  Focus on restoring pre-illness functional status is paramount.  Medical coding and billing will reflect the complexity of the patient's deconditioning and the planned rehabilitation services.