Starting activity with knee osteoarthritis and fear of falling
Mr. L is a 74-year-old retired postal worker with bilateral knee osteoarthritis, BMI 33 kg/m², and no regular exercise for 10 years. He can walk one block before knee pain reaches 6/10 and sometimes uses a cane outdoors. He has hypertension (142/86 mm Hg), an HbA1c of 6.1%, and no chest pain, but he is afraid of falling because a neighbor recently fractured a hip. He wants to get fit and lose weight but believes exercise will grind away his cartilage. He lives with his wife, who is supportive, and has a safe sidewalk and a community pool nearby. He asks whether he should start with walking, weights, or swimming, and how hard he should push when his knee hurts.
1. Write a specific physical activity prescription for Mr. L, including frequency, intensity, time, type, and progression.
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Prescribe low-impact, progressive activity rather than one modality. Frequency: 3–5 days/week aerobic; 2 nonconsecutive days/week strength; daily flexibility; balance 2–3 days/week. Aerobic: start 10–15 minutes of walking or aquatic exercise at 3–4/10 effort, build by 5 minutes every 1–2 weeks toward 30 minutes, 5 days/week (150 minutes/week). Type: walking on flat ground, stationary cycling, pool walking or swimming; avoid deep knee bends, running, and high-impact jumping initially. Strength: sit-to-stand, wall sits, leg curls, hip abduction, calf raises, 1–2 sets of 8–12 repetitions, pain no higher than 4/10. Use the cane outdoors. Progress by time before intensity. Warm up and cool down. His HbA1c of 6.1% does not require exercise restriction; BP 142/86 should be monitored. Refer to physical therapy for gait, quadriceps strengthening, and balance; consider aquatic physical therapy.
2. How would you assess and manage his fear of falling and knee pain so that he can adhere?
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Fear is a major predictor of inactivity. Assess fall risk with a Timed Up and Go, 30-second chair stand, and gait/balance examination; ask about prior falls, vision, footwear, home hazards, and medications. Explain that moderate exercise does not grind away cartilage and that strong quadriceps and gluteal muscles unload the knee. Set tiny goals (5 minutes, twice daily) and use pain-guided pacing: mild discomfort up to 4/10 during activity is acceptable if it settles within 24 hours; sharp pain, swelling, or locking is a reason to stop and reassess. Use a cane correctly, start supervised at the community pool, and involve his wife as a walking partner. Teach a relapse plan. Reassure that muscle soreness is expected. Screen for depression and catastrophic thinking; refer to physical therapy and, if needed, behavioral support.
3. What symptoms would prompt you to stop exercise and refer urgently?
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Stop and refer urgently for chest pain, pressure, or tightness; severe dyspnea; dizziness, syncope, or palpitations; new unilateral weakness, speech difficulty, or vision loss; calf pain or swelling; or sudden severe joint pain with inability to bear weight. Also stop for signs of hypoglycemia if he starts glucose-lowering therapy, or if BP is above 180/110 with symptoms. Otherwise, activity-related knee pain up to 4/10 that resolves with rest is not a reason to stop; adjust the load. Document an emergency plan and ensure he knows to call emergency services for chest pain or stroke symptoms.